From 8c42c25b90b10b2c5f20c93ebd9cf1df622b009f Mon Sep 17 00:00:00 2001 From: Gaetan Nadon Date: Fri, 25 Jun 2010 21:43:08 -0400 Subject: doc: replace groff input format with docbook xml format Initial version of SMlib and xsmp docbook xml. Requires util-macros 1.10 Signed-off-by: Gaetan Nadon --- configure.ac | 15 +- doc/.gitignore | 6 +- doc/Makefile.am | 76 +- doc/SMlib.ms | 2712 ------------------------------------------------------- doc/SMlib.xml | 2359 +++++++++++++++++++++++++++++++++++++++++++++++ doc/macros.t | 226 ----- doc/xsmp.ms | 1623 --------------------------------- doc/xsmp.xml | 1868 ++++++++++++++++++++++++++++++++++++++ 8 files changed, 4266 insertions(+), 4619 deletions(-) delete mode 100644 doc/SMlib.ms create mode 100644 doc/SMlib.xml delete mode 100644 doc/macros.t delete mode 100644 doc/xsmp.ms create mode 100644 doc/xsmp.xml diff --git a/configure.ac b/configure.ac index d4ee7c9..fd6b045 100644 --- a/configure.ac +++ b/configure.ac @@ -12,10 +12,15 @@ AM_INIT_AUTOMAKE([foreign dist-bzip2]) AM_MAINTAINER_MODE -# Require xorg-macros: XORG_DEFAULT_OPTIONS +# Require xorg-macros minimum of 1.10 for DocBook XML documentation m4_ifndef([XORG_MACROS_VERSION], - [m4_fatal([must install xorg-macros 1.6 or later before running autoconf/autogen])]) -XORG_MACROS_VERSION(1.6) + [m4_fatal([must install xorg-macros 1.10 or later before running autoconf/autogen])]) +XORG_MACROS_VERSION(1.10) +XORG_DEFAULT_OPTIONS +XORG_ENABLE_DOCS +XORG_WITH_XMLTO(0.0.20) +XORG_WITH_FOP +XORG_CHECK_SGML_DOCTOOLS(1.5) AM_CONFIG_HEADER([config.h]) @@ -23,10 +28,6 @@ AM_CONFIG_HEADER([config.h]) AC_PROG_LIBTOOL AC_PROG_CC -XORG_DEFAULT_OPTIONS -XORG_ENABLE_DOCS -XORG_WITH_GROFF - # Checks for pkg-config packages PKG_CHECK_MODULES(SM, [ice >= 1.0.5] xproto) AC_SUBST(SM_CFLAGS) diff --git a/doc/.gitignore b/doc/.gitignore index 84d7456..12fe512 100644 --- a/doc/.gitignore +++ b/doc/.gitignore @@ -1,8 +1,6 @@ # Add & Override for this directory and it's subdirectories *.html *.ps +*.pdf *.txt -*.html.raw -*.ps.raw -*.txt.raw -/images +*.css diff --git a/doc/Makefile.am b/doc/Makefile.am index 22657df..12a3c6e 100644 --- a/doc/Makefile.am +++ b/doc/Makefile.am @@ -1,5 +1,5 @@ # -# Copyright 2009 Sun Microsystems, Inc. All rights reserved. +# Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved. # # Permission is hereby granted, free of charge, to any person obtaining a # copy of this software and associated documentation files (the "Software"), @@ -21,62 +21,44 @@ # DEALINGS IN THE SOFTWARE. # -# Based on xc/doc/specs/SM/Makefile from X11R6.9 - -doc_sources = macros.t SMlib.ms xsmp.ms - -EXTRA_DIST = $(doc_sources) - if ENABLE_DOCS -if HAVE_GROFF_MS -doc_DATA = SMlib.txt SMlib.ps SMlib.html xsmp.txt xsmp.ps xsmp.html -imagesdir = $(docdir)/images +doc_sources = SMlib.xml xsmp.xml +dist_doc_DATA = $(doc_sources) -CLEANFILES = $(doc_DATA) -MOSTLYCLEANFILES = index.* +if HAVE_XMLTO +doc_DATA = $(doc_sources:.xml=.html) + +if HAVE_FOP +doc_DATA += $(doc_sources:.xml=.ps) $(doc_sources:.xml=.pdf) +endif -install-data-local: - test -z "$(imagesdir)" || $(mkdir_p) "$(DESTDIR)$(imagesdir)" - @d="$(srcdir)/images/"; \ - list=`ls $$d`; \ - for p in $$list; do \ - echo " $(INSTALL_DATA) '$$d$$p' '$(DESTDIR)$(imagesdir)/$$p'"; \ - $(INSTALL_DATA) "$$d$$p" "$(DESTDIR)$(imagesdir)/$$p"; \ - done; +if HAVE_XMLTO_TEXT +doc_DATA += $(doc_sources:.xml=.txt) +endif -uninstall-local: - @if test -n $(DESTDIR)$(imagesdir); then \ - if test -d $(DESTDIR)$(imagesdir); then \ - list=`ls $(DESTDIR)$(imagesdir)`; \ - for p in $$list; do \ - echo " rm -f '$(DESTDIR)$(imagesdir)/$$p'"; \ - rm -f "$(DESTDIR)$(imagesdir)/$$p"; \ - done \ - fi; \ - fi; +if HAVE_STYLESHEETS +XMLTO_FLAGS = -m $(XSL_STYLESHEET) -mostlyclean-local: - @rm -fr images +doc_DATA += xorg.css +xorg.css: $(STYLESHEET_SRCDIR)/xorg.css + $(AM_V_GEN)cp -pf $(STYLESHEET_SRCDIR)/xorg.css $@ +endif -# Pass version string as a troff string for substitution -GROFF_DEFS = -dxV="$(PACKAGE_STRING)" +CLEANFILES = $(doc_DATA) -# -t to run through tbl -GROFF_FLAGS = -t -ms $(GROFF_DEFS) $(srcdir)/macros.t +SUFFIXES = .xml .ps .pdf .txt .html -SUFFIXES = .ms .ps .txt .html +.xml.txt: + $(AM_V_GEN)$(XMLTO) $(XMLTO_FLAGS) txt $< -.ms.ps: - -$(AM_V_GEN) $(GROFF) -Tps $(GROFF_FLAGS) $< 2> index.$@.raw > $@ - @if grep '^[^1-9.]' index.$@.raw | grep -v warning; then exit 1; \ - else test $$? -le 1; fi +.xml.html: + $(AM_V_GEN)$(XMLTO) $(XMLTO_FLAGS) xhtml-nochunks $< -.ms.txt: - $(AM_V_GEN) env GROFF_NO_SGR=TRUE $(GROFF) -Tutf8 $(GROFF_FLAGS) \ - $< 2> index.$@.raw > $@ +.xml.pdf: + $(AM_V_GEN)$(XMLTO) $(XMLTO_FLAGS) --with-fop pdf $< -.ms.html: - $(AM_V_GEN) $(GROFF) -Thtml -P-Dimages -P-I$*-image $(GROFF_FLAGS) $< 2> index.$@.raw > $@ +.xml.ps: + $(AM_V_GEN)$(XMLTO) $(XMLTO_FLAGS) --with-fop ps $< -endif HAVE_GROFF_MS +endif HAVE_XMLTO endif ENABLE_DOCS diff --git a/doc/SMlib.ms b/doc/SMlib.ms deleted file mode 100644 index 57876ba..0000000 --- a/doc/SMlib.ms +++ /dev/null @@ -1,2712 +0,0 @@ -.\" $Xorg: SMlib.ms,v 1.3 2000/08/17 19:42:19 cpqbld Exp $ -.\" $XdotOrg: xc/doc/specs/SM/SMlib.ms,v 1.2 2004/04/23 18:42:16 eich Exp $ -.\" -.\" Use tbl, -ms, and macros.t -.\" edited for DP edits and code consistency w/ core protocol/xlib 4/18/96 -.\" macro: start marker -.de sM -.ne 4 -.sp 1 -\\h'-0.3i'\\L'-1v'\\v'3p'\\l'1v'\\v'1v-3p' -.sp -1 -.. -.\" macro: end marker -.de eM -.sp -1 -\\h'-0.3i'\\L'-1v'\\v'1v+4p'\\l'1v'\\v'-4p' -.sp 1 -.. -.EH '''' -.OH '''' -.EF '''' -.OF '''' -.ad b -.sp 10 -.TL -\s+2\fBX Session Management Library\fP\s-2 -.sp -Version 1.0 -.sp -X Consortium Standard -.sp -X Version 11, Release 7 -.sp -\*(xV -.AU -Ralph Mor -.AI -X Consortium -.LP -.DS C -Copyright \(co 1993, 1994 X Consortium -.DE -.LP -.sp 5 -Permission is hereby granted, free of charge, to any person obtaining a copy -of this software and associated documentation files (the ``Software''), to deal -in the Software without restriction, including without limitation the rights -to use, copy, modify, merge, publish, distribute, sublicense, and/or sell -copies of the Software, and to permit persons to whom the Software is -furnished to do so, subject to the following conditions: -.LP -The above copyright notice and this permission notice shall be included in -all copies or substantial portions of the Software. -.LP -THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR -IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, -FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE -X CONSORTIUM BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN -AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN -CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. -.LP -Except as contained in this notice, the name of the X Consortium shall not be -used in advertising or otherwise to promote the sale, use or other dealings -in this Software without prior written authorization from the X Consortium. -.sp 3 -X Window System is a trademark of The Open Group. -.bp -.bp 1 -.EH '\fBX Session Management Library\fP''\fB\*(xV\fP' -.OH '\fBX Session Management Library\fP''\fB\*(xV\fP' -.EF ''\- \\\\n(PN \-'' -.OF ''\- \\\\n(PN \-'' -.NH 1 -Overview of Session Management -.XS -\*(SN Overview of Session Management -.XE -.LP -The purpose of the X Session Management Protocol (XSMP) is to provide a -uniform mechanism for users to save and restore their sessions. A -\fIsession\fP is a group of clients, each of which has a particular state. -The session is controlled by a network service called the \fIsession -manager\fP\^. The session manager issues commands to its clients on behalf -of the user. These commands may cause clients to save their state or to -terminate. It is expected that the client will save its state in such a -way that the client can be restarted at a later time and resume its -operation as if it had never been terminated. A client's state might -include information about the file currently being edited, the current -position of the insertion point within the file, or the start of an -uncommitted transaction. The means by which clients are restarted is -unspecified by this protocol. -.LP -For purposes of this protocol, a \fIclient\fP\^ of the session manager is -defined as a connection to the session manager. A client is typically, -though not necessarily, a process running an application program connected -to an X display. However, a client may be connected to more -than one X display or not be connected to any X displays at all. -.NH 1 -The Session Management Library -.XS -\*(SN The Session Management Library -.XE -.LP -The Session Management Library (SMlib) is a low-level "C" language -interface to XSMP. It is expected that higher level toolkits, such as -Xt, will hide many of -the details of session management from clients. Higher level toolkits -might also be developed for session managers to use, but no such effort -is currently under way. -.LP -SMlib has two parts to it: -.IP \(bu 5 -One set of functions for clients that want to be part of a session -.IP \(bu 5 -One set of functions for session managers to call -.LP -Some applications will use both sets of functions and act as \fInested -session managers\fP\^. -That is, they will be both a session manager and a client of another session. -An example is a mail program that could start a text editor for editing -the text of a mail message. The mail program is part of -a regular session and, at the same time, is also acting as a session manager -to the editor. -.LP -Clients initialize by connecting to the session manager and obtaining -a \fIclient-ID\fP\^ that uniquely identifies them in the session. -The session manager maintains a list of properties for each client in -the session. These properties describe the client's environment -and, most importantly, describe how the client can be restarted (via an -.PN SmRestartCommand ). -Clients are expected to save their state in such a way as to allow multiple -instantiations of themselves to be managed independently. For example, -clients may use their client-ID as part of a filename in which -to store the state for a particular instantiation. The client-ID -should be saved as part of the -.PN SmRestartCommand -so that the client will retain the same ID after it is restarted. -.LP -Once the client initializes itself with the session manager, it must be -ready to respond to messages from the session manager. For example, it -might be asked to save its state or to terminate. In the case of a shutdown, -the session manager might give each client a chance to interact with the -user and cancel the shutdown. -.NH 1 -Understanding SMlib's Dependence on ICE -.XS -\*(SN Understanding SMlib's Dependence on ICE -.XE -.LP -The X Session Management Protocol is layered on top of the Inter-Client -Exchange (ICE) Protocol. The ICE protocol is designed to multiplex several -protocols over a single connection. As a result, working with SMlib requires -a little knowledge of how the ICE library works. -.LP -The ICE library utilizes callbacks to process messages. When a client -detects that there is data to read on an ICE connection, it should call -the -.PN IceProcessMessages -function. -.PN IceProcessMessages -will read the message header and look at the major opcode in order -to determine which protocol the message was intended for. The appropriate -protocol library will then be triggered to unpack the message and hand it -off to the client via a callback. -.LP -The main point to be aware of is that an application using SMlib must -have some code that detects when there is data to read on an ICE connection. -This can be done via a -.PN select -call on the file descriptor for the ICE connection, but more typically, -.PN XtAppAddInput -will be used to register a callback that will invoke -.PN IceProcessMessages -each time there is data to read on the ICE connection. -.LP -To further complicate things, knowing which file descriptors to call -.PN select -on requires an understanding of how ICE connections are created. -On the client side, a call must be made to -.PN SmcOpenConnection -in order to open a connection with a session manager. -.PN SmcOpenConnection -will internally make a call into -.PN IceOpenConnection , -which will, in turn, determine if an ICE connection already exists between -the client and session manager. Most likely, a connection will not already -exist and a new ICE connection will be created. The main point to be aware -of is that, on the client side, it is not obvious when ICE connections get -created or destroyed, because connections are shared when possible. -To deal with this, the ICE library lets the application register -watch procedures that will be invoked each time an ICE connection -is opened or closed. -These watch procedures could be used to add or remove ICE file descriptors -from the list of descriptors to call -.PN select -on. -.LP -On the session manager side, things work a bit differently. The session -manager has complete control over the creation -of ICE connections. The session manager has to first call -.PN IceListenForConnections -in order to start listening for connections from clients. Once a connection -attempt is detected, -.PN IceAcceptConnection -must be called, and the session manager can simply add the new ICE -file descriptor to the list of descriptors to call -.PN select -on. -.LP -For further information on the library functions related to ICE connections, -see the \fIInter-Client Exchange Library\fP\^ standard. -.NH 1 -Header Files and Library Name -.XS -\*(SN Header Files and Library Name -.XE -.LP -Applications (both session managers and clients) should include the -header file -.Pn < X11/SM/SMlib.h >. -This header file defines all of the SMlib data structures -and function prototypes. -.PN SMlib.h -includes the header file -.Pn < X11/SM/SM.h >, -which defines all of the SMlib constants. -.LP -Because SMlib is dependent on ICE, applications should link against -SMlib and ICElib by using -.PN -lSM -.PN -lICE . -.NH 1 -Session Management Client (Smc) Functions -.XS -\*(SN Session Management Client (Smc) Functions -.XE -.LP -This section discusses how Session Management clients: -.IP \(bu 5 -Connect to the Session Manager -.IP \(bu 5 -Close the connection -.IP \(bu 5 -Modify callbacks -.IP \(bu 5 -Set, delete, and retrieve Session Manager properties -.IP \(bu 5 -Interact with the user -.IP \(bu 5 -Request a ``Save Yourself'' -.IP \(bu 5 -Request a ``Save Yourself Phase 2'' -.IP \(bu 5 -Complete a ``Save Yourself'' -.IP \(bu 5 -Use Smc informational functions -.IP \(bu 5 -Handle Errors -.NH 2 -Connecting to the Session Manager -.XS -\*(SN Connecting to the Session Manager -.XE -.LP -To open a connection with a session manager, use -.PN SmcOpenConnection . -.sM -.FD 0 -SmcConn SmcOpenConnection\^(\^\fInetwork_ids_list\fP, \fIcontext\fP\^, \fIxsmp_major_rev\fP\^, \fIxsmp_minor_rev\fP\^, -.br - \fImask\fP\^, \fIcallbacks\fP\^, \fIprevious_id\fP\^, \fIclient_id_ret\fP\^, \fIerror_length\fP\^, \fIerror_string_ret\fP\^) -.br - char *\fInetwork_ids_list\fP\^; -.br - SmPointer \fIcontext\fP\^; -.br - int \fIxsmp_major_rev\fP\^; -.br - int \fIxsmp_minor_rev\fP\^; -.br - unsigned long \fImask\fP\^; -.br - SmcCallbacks *\fIcallbacks\fP\^; -.br - char *\fIprevious_id\fP\^; -.br - char **\fIclient_id_ret\fP\^; -.br - int \fIerror_length\fP\^; -.br - char *\fIerror_string_ret\fP\^; -.FN -.IP \fInetwork_ids_list\fP 1i -Specifies the network ID(s) of the session manager. -.IP \fIcontext\fP 1i -A pointer to an opaque object or NULL. Used to determine if an -ICE connection can be shared (see below). -.IP \fIxsmp_major_rev\fP 1i -The highest major version of the XSMP the application supports. -.IP \fIxsmp_minor_rev\fP 1i -The highest minor version of the XSMP the application supports (for the -specified xsmp_major_rev). -.IP \fImask\fP\^ 1i -A mask indicating which callbacks to register. -.IP \fIcallbacks\fP 1i -The callbacks to register. These callbacks are used to respond to messages -from the session manager. -.IP \fIprevious_id\fP 1i -The client ID from the previous session. -.IP \fIclient_id_ret\fP 1i -The client ID for the current session is returned. -.IP \fIerror_length\fP 1i -Length of the error_string_ret argument passed in. -.IP \fIerror_string_ret\fP 1i -Returns a null-terminated error message, if any. -The error_string_ret argument points to user supplied memory. -No more than error_length bytes are used. -.LP -.eM -The network_ids_list argument is a null-terminated string containing a list of -network IDs for the session manager, separated by commas. -If network_ids_list is NULL, -the value of the -.PN SESSION_MANAGER -environment variable will be used. -Each network ID has the following format: -.TS -lw(0.25i) lw(2.5i) lw(1i). - tcp/: or - decnet/:: or - local/: -.TE -.LP -An attempt will be made to use the first network ID. If that fails, -an attempt will be made using the second network ID, and so on. -.LP -After the connection is established, -.PN SmcOpenConnection -registers the client with the session manager. If the client is being -restarted from a previous session, previous_id should contain a null -terminated string representing the client ID from the previous session. -If the client is first joining the session, previous_id should be -set to NULL. -If previous_id is specified but is determined to be invalid by the -session manager, SMlib will re-register -the client with previous_id set to NULL. -.LP -If -.PN SmcOpenConnection -succeeds, it returns an opaque connection pointer of type -.PN SmcConn -and the client_id_ret argument contains the client ID to be used for -this session. -The client_id_ret should be freed with a call to -.PN free -when no longer needed. On failure, -.PN SmcOpenConnection -returns NULL, -and the reason for failure is returned in error_string_ret. -.LP -Note that SMlib uses the ICE protocol to establish a connection with -the session manager. If an ICE connection already exists between the -client and session manager, it might be possible for the same ICE connection -to be used for session management. -.LP -The context argument indicates how willing the client is to share -the ICE connection with other protocols. If context is NULL, -then the caller is always willing to share the connection. -If context is not NULL, -then the caller is not willing to use a previously opened ICE connection -that has a different non-NULL context associated with it. -.LP -As previously discussed (section 3, ``Understanding SMlib's Dependence -on ICE''), the client will have to keep track of when ICE connections -are created or destroyed (using -.PN IceAddConnectionWatch -and -.PN IceRemoveConnectionWatch ), -and will have to call -.PN IceProcessMessages -each time a -.PN select -shows that there is data to read on an ICE connection. -For further information, see the -\fIInter-Client Exchange Library\fP\^ standard. -.LP -The callbacks argument contains a set of callbacks used to respond to session -manager events. The mask argument specifies which callbacks are set. -All of the callbacks specified in this version of SMlib are mandatory. The -mask argument is necessary in order to maintain backwards compatibility -in future versions of the library. -.LP -The following values may be ORed together to obtain a mask value: -.LP -.Ds 0 -.PN SmcSaveYourselfProcMask -.PN SmcDieProcMask -.PN SmcSaveCompleteProcMask -.PN SmcShutdownCancelledProcMask -.De -.LP -For each callback, the client can register a pointer to client data. -When SMlib invokes the callback, it will pass the client data pointer. -.LP -.sM -.Ds 0 -.TA .5i 1i 1.5i -.ta .5i 1i 1.5i -typedef struct { - - struct { - SmcSaveYourselfProc callback; - SmPointer client_data; - } save_yourself; - - struct { - SmcDieProc callback; - SmPointer client_data; - } die; - - struct { - SmcSaveCompleteProc callback; - SmPointer client_data; - } save_complete; - - struct { - SmcShutdownCancelledProc callback; - SmPointer client_data; - } shutdown_cancelled; - -} SmcCallbacks; -.De -.LP -.eM -.NH 3 -The Save Yourself Callback -.XS -\*(SN The Save Yourself Callback -.XE -.LP -The Save Yourself callback is of type -.PN SmcSaveYourselfProc . -.sM -.FD 0 -typedef void (*SmcSaveYourselfProc)(); - -void SaveYourselfProc\^(\^\fIsmc_conn\fP, \fIclient_data\fP\^, \fIsave_type\fP\^, \fIshutdown\fP\^, \fIinteract_style\fP\^, \fIfast\fP\^) -.br - SmcConn \fIsmc_conn\fP\^; -.br - SmPointer \fIclient_data\fP\^; -.br - int \fIsave_type\fP\^; -.br - Bool \fIshutdown\fP\^; -.br - int \fIinteract_style\fP\^; -.br - Bool \fIfast\fP\^; -.FN -.IP \fIsmc_conn\fP 1i -The session management connection object. -.IP \fIclient_data\fP 1i -Client data specified when the callback was registered. -.IP \fIsave_type\fP 1i -Specifies the type of information that should be saved. -.IP \fIshutdown\fP 1i -Specifies if a shutdown is taking place. -.IP \fIinteract_style\fP 1i -The type of interaction allowed with the user. -.IP \fIfast\fP 1i -If -.PN True , -the client should save its state as quickly as possible. -.LP -.eM -The session manager sends a ``Save Yourself'' message to a client -either to checkpoint it or just before -termination so that it can save its state. -The client responds with zero or more calls to -.PN SmcSetProperties -to update the properties indicating how to restart the client. -When all the properties have been set, the client calls -.PN SmcSaveYourselfDone . -.LP -If interact_style is -.PN SmInteractStyleNone , -the client must not interact with the -user while saving state. -If interact_style is -.PN SmInteractStyleErrors , -the client may interact with the user only if an error condition arises. -If interact_style is -.PN SmInteractStyleAny , -then the client may interact with the user for any purpose. -Because only one client can interact with the user at a time, -the client must call -.PN SmcInteractRequest -and wait for an ``Interact'' message from the session manager. -When the client is done interacting with the user, it calls -.PN SmcInteractDone . -The client may only call -.PN SmcInteractRequest -after it receives a ``Save Yourself'' message and before it -calls -.PN SmcSaveYourselfDone . -.LP -If save_type is -.PN SmSaveLocal , -the client must update the properties to reflect its current state. -Specifically, it should save enough information to restore -the state as seen by the user of this client. It should not affect the -state as seen by other users. If save_type is -.PN SmSaveGlobal , -the user wants the client to commit all of its data to permanent, -globally accessible storage. If save_type is -.PN SmSaveBoth , -the client should do both of these (it should first commit the data to -permanent storage before updating its properties). -.LP -Some examples are as follows: -.LP -.IP \(bu 5 -If a word processor were sent a ``Save Yourself'' with a type of -.PN SmSaveLocal , -it could create a temporary file that included the -current contents of the file, the location of the cursor, and -other aspects of the current editing session. -It would then update its SmRestartCommand property -with enough information to find this temporary file. -.IP \(bu 5 -If a word processor were sent a ``Save Yourself'' with a type of -.PN SmSaveGlobal , -it would simply save the currently edited file. -.IP \(bu 5 -If a word processor were sent a ``Save Yourself'' with a type of -.PN SmSaveBoth , -it would first save the currently edited file. -It would then create a temporary file with information -such as the current position of the cursor -and what file is being edited. -Finally, it would update its SmRestartCommand property -with enough information to find the temporary file. -.LP -The shutdown argument specifies whether the system is being -shut down. The interaction is different depending on whether or not -shutdown is set. If not shutting down, the client should save its -state and wait for a ``Save Complete'' message. If shutting down, -the client must save state and -then prevent interaction until it receives either a ``Die'' -or a ``Shutdown Cancelled.'' -.LP -The fast argument specifies that the client should save its state -as quickly as possible. For example, if the session manager knows that -power is about to fail, it would set fast to -.PN True . -.NH 3 -The Die Callback -.XS -\*(SN The Die Callback -.XE -.LP -The Die callback is of type -.PN SmcDieProc . -.sM -.FD 0 -typedef void (*SmcDieProc)(); - -void DieProc\^(\^\fIsmc_conn\fP, \fIclient_data\fP\^) -.br - SmcConn \fIsmc_conn\fP\^; -.br - SmPointer \fIclient_data\fP\^; -.FN -.IP \fIsmc_conn\fP 1i -The session management connection object. -.IP \fIclient_data\fP 1i -Client data specified when the callback was registered. -.LP -.eM -The session manager sends a ``Die'' message to a client -when it wants it to die. The client should respond by calling -.PN SmcCloseConnection . -A session manager that behaves properly will send a -``Save Yourself'' message before the ``Die'' message. -.NH 3 -The Save Complete Callback -.XS -\*(SN The Save Complete Callback -.XE -.LP -The Save Complete callback is of type -.PN SmcSaveCompleteProc . -.sM -.FD 0 -typedef void (*SmcSaveCompleteProc)(); - -void SaveCompleteProc\^(\^\fIsmc_conn\fP, \fIclient_data\fP\^) -.br - SmcConn \fIsmc_conn\fP\^; -.br - SmPointer \fIclient_data\fP\^; -.FN -.IP \fIsmc_conn\fP 1i -The session management connection object. -.IP \fIclient_data\fP 1i -Client data specified when the callback was registered. -.LP -.eM -When the session manager is done with a checkpoint, it will send each of -the clients a ``Save Complete'' message. The client is then free to -change its state. -.NH 3 -The Shutdown Cancelled Callback -.XS -\*(SN The Shutdown Cancelled Callback -.XE -.LP -The Shutdown Cancelled callback is of type -.PN SmcShutdownCancelledProc . -.sM -.FD 0 -typedef void (*SmcShutdownCancelledProc)(); - -void ShutdownCancelledProc\^(\^\fIsmc_conn\fP, \fIclient_data\fP\^) -.br - SmcConn \fIsmc_conn\fP\^; -.br - SmPointer \fIclient_data\fP\^; -.FN -.IP \fIsmc_conn\fP 1i -The session management connection object. -.IP \fIclient_data\fP 1i -Client data specified when the callback was registered. -.LP -.eM -The session manager sends a ``Shutdown Cancelled'' message -when the user cancelled the shutdown during an interaction -(see section 5.5, ``Interacting With the User''). -The client can now continue as if the shutdown had never happened. -If the client has not called -.PN SmcSaveYourselfDone -yet, it can either abort the save and then call -.PN SmcSaveYourselfDone -with the success argument set to -.PN False , -or it can continue with the save and then call -.PN SmcSaveYourselfDone -with the success argument set to reflect the outcome of the save. -.NH 2 -Closing the Connection -.XS -\*(SN Closing the Connection -.XE -.LP -To close a connection with a session manager, use -.PN SmcCloseConnection . -.LP -.sM -.FD 0 -SmcCloseStatus SmcCloseConnection\^(\^\fIsmc_conn\fP, \fIcount\fP\^, \fIreason_msgs\fP\^) -.br - SmcConn \fIsmc_conn\fP\^; -.br - int \fIcount\fP\^; -.br - char **\fIreason_msgs\fP\^; -.FN -.IP \fIsmc_conn\fP 1i -The session management connection object. -.IP \fIcount\fP 1i -The number of reason messages. -.IP \fIreason_msgs\fP 1i -The reasons for closing the connection. -.LP -.eM -The reason_msgs argument will most likely be NULL if resignation -is expected by the client. -Otherwise, it contains a list of null-terminated Compound Text strings -representing the reason for termination. -The session manager should display these reason messages -to the user. -.LP -Note that SMlib used the ICE protocol to establish a connection with -the session manager, and various protocols other than session management -may be active on the ICE connection. When -.PN SmcCloseConnection -is called, the ICE connection will be closed only if all protocols -have been shutdown on the connection. Check the ICElib -standard for -.PN IceAddConnectionWatch -and -.PN IceRemoveConnectionWatch -to learn how to set up a callback to be invoked each time an ICE connection is -opened or closed. Typically this callback adds/removes the ICE file -descriptor from the list of active descriptors to call -.PN select -on (or calls -.PN XtAppAddInput -or -.PN XtRemoveInput ). -.LP -.PN SmcCloseConnection -returns one of the following values: -.IP \(bu 5 -.PN SmcClosedNow -\- the ICE connection was closed at this time, the watch procedures were -invoked, and the connection was freed. -.IP \(bu 5 -.PN SmcClosedASAP -\- an IO error had occurred on the connection, but -.PN SmcCloseConnection -is being called within a nested -.PN IceProcessMessages . -The watch procedures have been invoked at this time, but the connection -will be freed as soon as possible (when the nesting level reaches zero and -.PN IceProcessMessages -returns a status of -.PN IceProcessMessagesConnectionClosed ). -.IP \(bu 5 -.PN SmcConnectionInUse -\- the connection was not closed at this time, because it is being used by -other active protocols. -.NH 2 -Modifying Callbacks -.XS -\*(SN Modifying Callbacks -.XE -.LP -To modify callbacks set up in -.PN SmcOpenConnection , -use -.PN SmcModifyCallbacks . -.sM -.FD 0 -void SmcModifyCallbacks\^(\^\fIsmc_conn\fP, \fImask\fP\^, \fIcallbacks\fP\^) -.br - SmcConn \fIsmc_conn\fP\^; -.br - unsigned long \fImask\fP\^; -.br - SmcCallbacks *\fIcallbacks\fP\^; -.FN -.IP \fIsmc_conn\fP 1i -The session management connection object. -.IP \fImask\fP 1i -A mask indicating which callbacks to modify. -.IP \fIcallbacks\fP 1i -The new callbacks. -.LP -.eM -When specifying a value for the mask argument, the following -values may be ORed together: -.LP -.Ds 0 -.PN SmcSaveYourselfProcMask -.PN SmcDieProcMask -.PN SmcSaveCompleteProcMask -.PN SmcShutdownCancelledProcMask -.De -.NH 2 -Setting, Deleting, and Retrieving Session Management Properties -.XS -\*(SN Setting, Deleting, and Retrieving Session Management Properties -.XE -.LP -To set session management properties for this client, use -.PN SmcSetProperties . -.sM -.FD 0 -void SmcSetProperties\^(\^\fIsmc_conn\fP, \fInum_props\fP\^, \fIprops\fP\^) -.br - SmcConn \fIsmc_conn\fP\^; -.br - int \fInum_props\fP\^; -.br - SmProp **\fIprops\fP\^; -.FN -.IP \fIsmc_conn\fP 1i -The session management connection object. -.IP \fInum_props\fP 1i -The number of properties. -.IP \fIprops\fP 1i -The list of properties to set. -.LP -.eM -The properties are specified as an array of property pointers. -Previously set property values may be over-written using the -.PN SmcSetProperties -function. Note that the session manager is not -expected to restore property values when the session is restarted. Because -of this, clients should not try to use the session manager as -a database for storing application specific state. -.LP -For a description of session management properties and the -.PN SmProp -structure, see section 7, ``Session Management Properties.'' -.sp -.LP -To delete properties previously set by the client, use -.PN SmcDeleteProperties . -.sM -.FD 0 -void SmcDeleteProperties\^(\^\fIsmc_conn\fP, \fInum_props\fP\^, \fIprop_names\fP\^) -.br - SmcConn \fIsmc_conn\fP\^; -.br - int \fInum_props\fP\^; -.br - char **\fIprop_names\fP\^; -.FN -.IP \fIsmc_conn\fP 1i -The session management connection object. -.IP \fInum_props\fP 1i -The number of properties. -.IP \fIprop_names\fP 1i -The list of properties to delete. -.LP -.eM -.LP -To get properties previously stored by the client, use -.PN SmcGetProperties . -.sM -.FD 0 -Status SmcGetProperties\^(\^\fIsmc_conn\fP, \fIprop_reply_proc\fP\^, \fIclient_data\fP\^) -.br - SmcConn \fIsmc_conn\fP\^; -.br - SmcPropReplyProc \fIprop_reply_proc\fP\^; -.br - SmPointer \fIclient_data\fP\^; -.FN -.IP \fIsmc_conn\fP 1i -The session management connection object. -.IP \fIprop_reply_proc\fP 1i -The callback to be invoked when the properties reply comes back. -.IP \fIclient_data\fP 1i -This pointer to client data will be passed to the -.PN SmcPropReplyProc -callback. -.LP -.eM -The return value of -.PN SmcGetProperties -is zero for failure and a positive value for success. -.LP -Note that the library does not block until the properties reply comes back. -Rather, a callback of type -.PN SmcPropReplyProc -is invoked when the data is ready. -.sM -.FD 0 -typedef void (*SmcPropReplyProc)(); - -void PropReplyProc\^(\^\fIsmc_conn\fP, \fIclient_data\fP\^, \fInum_props\fP\^, \fIprops\fP\^) -.br - SmcConn \fIsmc_conn\fP\^; -.br - SmPointer \fIclient_data\fP\^; -.br - int \fInum_props\fP\^; -.br - SmProp **\fIprops\fP\^; -.FN -.IP \fIsmc_conn\fP 1i -The session management connection object. -.IP \fIclient_data\fP 1i -Client data specified when the callback was registered. -.IP \fInum_props\fP 1i -The number of properties returned. -.IP \fIprops\fP 1i -The list of properties returned. -.LP -.eM -To free each property, use -.PN SmFreeProperty -(see section 8, ``Freeing Data''). -To free the actual array of pointers, use -.PN free . -.NH 2 -Interacting With the User -.XS -\*(SN Interacting With the User -.XE -.LP -After receiving a ``Save Yourself'' message with an interact_style of -.PN SmInteractStyleErrors -or -.PN SmInteractStyleAny , -the client may choose to interact with the user. -Because only one client can interact with the user at a time, the client -must call -.PN SmcInteractRequest -and wait for an ``Interact'' message from the session manager. -.sM -.FD 0 -Status SmcInteractRequest\^(\^\fIsmc_conn\fP, \fIdialog_type\fP\^, \fIinteract_proc\fP\^, \fIclient_data\fP\^) -.br - SmcConn \fIsmc_conn\fP\^; -.br - int \fIdialog_type\fP\^; -.br - SmcInteractProc \fIinteract_proc\fP\^; -.br - SmPointer \fIclient_data\fP\^; -.FN -.IP \fIsmc_conn\fP 1i -The session management connection object. -.IP \fIdialog_type\fP 1i -The type of dialog the client wishes to present to the user. -.IP \fIinteract_proc\fP 1i -The callback to be invoked when the ``Interact'' message arrives from -the session manager. -.IP \fIclient_data\fP 1i -This pointer to client data will be passed to the -.PN SmcInteractProc -callback when the ``Interact'' message arrives. -.LP -.eM -The return value of -.PN SmcInteractRequest -is zero for failure and a positive value for success. -.LP -The dialog_type argument specifies either -.PN SmDialogError , -indicating that the client wants to start an error dialog, or -.PN SmDialogNormal , -meaning that the client wishes to start a nonerror dialog. -.LP -Note that if a shutdown is in progress, the user may have the option of -cancelling the shutdown. If the shutdown is cancelled, the clients that -have not interacted yet with the user will receive a -``Shutdown Cancelled'' message instead of the ``Interact'' message. -.LP -The -.PN SmcInteractProc -callback will be invoked when the ``Interact'' message arrives from -the session manager. -.sM -.FD 0 -typedef void (*SmcInteractProc)(); - -void InteractProc\^(\^\fIsmc_conn\fP, \fIclient_data\fP\^) -.br - SmcConn \fIsmc_conn\fP\^; -.br - SmPointer \fIclient_data\fP\^; -.FN -.IP \fIsmc_conn\fP 1i -The session management connection object. -.IP \fIclient_data\fP 1i -Client data specified when the callback was registered. -.LP -.eM -.LP -After interacting with the user (in response to an ``Interact'' message), -you should call -.PN SmcInteractDone . -.sM -.FD 0 -void SmcInteractDone\^(\^\fIsmc_conn\fP, \fIcancel_shutdown\fP\^) -.br - SmcConn \fIsmc_conn\fP\^; -.br - Bool \fIcancel_shutdown\fP\^; -.FN -.IP \fIsmc_conn\fP 1i -The session management connection object. -.IP \fIcancel_shutdown\fP 1i -If -.PN True , -indicates that the user requests that the entire shutdown be cancelled. -.LP -.eM -The cancel_shutdown argument may only be -.PN True -if the corresponding ``Save Yourself'' specified -.PN True -for shutdown and -.PN SmInteractStyleErrors -or -.PN SmInteractStyleAny -for the interact_style. -.NH 2 -Requesting a Save Yourself -.XS -\*(SN Requesting a Save Yourself -.XE -.LP -To request a checkpoint from the session manager, use -.PN SmcRequestSaveYourself . -.sM -.FD 0 -void SmcRequestSaveYourself\^(\^\fIsmc_conn\fP, \fIsave_type\fP\^, \fIshutdown\fP\^, \fIinteract_style\fP\^, \fIfast\fP\^, \fIglobal\fP\^) -.br - SmcConn \fIsmc_conn\fP\^; -.br - int \fIsave_type\fP\^; -.br - Bool \fIshutdown\fP\^; -.br - int \fIinteract_style\fP\^; -.br - Bool \fIfast\fP\^; -.br - Bool \fIglobal\fP\^; -.FN -.IP \fIsmc_conn\fP 1i -The session management connection object. -.IP \fIsave_type\fP 1i -Specifies the type of information that should be saved. -.IP \fIshutdown\fP 1i -Specifies if a shutdown is taking place. -.IP \fIinteract_style\fP 1i -The type of interaction allowed with the user. -.IP \fIfast\fP 1i -If -.PN True , -the client should save its state as quickly as possible. -.IP \fIglobal\fP 1i -Controls who gets the ``Save Yourself.'' -.LP -.eM -The save_type, shutdown, interact_style, and -fast arguments are discussed in more detail in section 5.1.1, -``The Save Yourself Callback.'' -.LP -If global is set to -.PN True , -then the resulting ``Save Yourself'' should be -sent to all clients in the session. For example, a vendor of a -Uninterruptible Power Supply (UPS) might include a Session -Management client that would monitor the status of the UPS -and generate a fast shutdown if the power is about to be lost. -.LP -If global is set to -.PN False , -then the ``Save Yourself'' should only be sent to the client that -requested it. -.NH 2 -Requesting a Save Yourself Phase 2 -.XS -\*(SN Requesting a Save Yourself Phase 2 -.XE -.LP -In response to a ``Save Yourself, the client may request to be informed -when all the other clients are quiescent so that it can save their state. -To do so, use -.PN SmcRequestSaveYourselfPhase2 . -.sM -.FD 0 -Status SmcRequestSaveYourselfPhase2\^(\^\fIsmc_conn\fP, \fIsave_yourself_phase2_proc\fP\^, \fIclient_data\fP\^) -.br - SmcConn \fIsmc_conn\fP\^; -.br - SmcSaveYourselfPhase2Proc \fIsave_yourself_phase2_proc\fP\^; -.br - SmPointer \fIclient_data\fP\^; -.FN -.IP \fIsmc_conn\fP 1i -The session management connection object. -.IP \fIsave_yourself_phase2_proc\fP 1i -The callback to be invoked when the ``Save Yourself Phase 2'' message -arrives from the session manager. -.IP \fIclient_data\fP 1i -This pointer to client data will be passed to the -.PN SmcSaveYourselfPhase2Proc -callback when the ``Save Yourself Phase 2'' message arrives. -.LP -.eM -The return value of -.PN SmcRequestSaveYourselfPhase2 -is zero for failure and a positive value for success. -.LP -This request is needed by clients that manage other clients (for example, -window managers, workspace managers, and so on). -The manager must make sure that all of the clients that are being managed -are in an idle state so that their state can be saved. -.NH 2 -Completing a Save Yourself -.XS -\*(SN Completing a Save Yourself -.XE -.LP -After saving state in response to a ``Save Yourself'' message, -you should call -.PN SmcSaveYourselfDone . -.sM -.FD 0 -void SmcSaveYourselfDone\^(\^\fIsmc_conn\fP, \fIsuccess\fP\^) -.br - SmcConn \fIsmc_conn\fP\^; -.br - Bool \fIsuccess\fP\^; -.FN -.IP \fIsmc_conn\fP 1i -The session management connection object. -.IP \fIsuccess\fP 1i -If -.PN True , -the ``Save Yourself'' operation was completed successfully. -.LP -.eM -Before calling -.PN SmcSaveYourselfDone , -the client must have set each required property at least once since -the client registered with the session manager. -.NH 2 -Using Smc Informational Functions -.XS -\*(SN Using Smc Informational Functions -.XE -.LP -.sM -.FD 0 -int SmcProtocolVersion\^(\^\fIsmc_conn\fP\^) -.br - SmcConn \fIsmc_conn\fP\^; -.FN -.eM -.PN SmcProtocolVersion -returns the major version of the session management protocol -associated with this session. -.sp -.LP -.sM -.FD 0 -int SmcProtocolRevision\^(\^\fIsmc_conn\fP\^) -.br - SmcConn \fIsmc_conn\fP\^; -.FN -.eM -.PN SmcProtocolRevision -returns the minor version of the session management protocol -associated with this session. -.sp -.LP -.sM -.FD 0 -char *SmcVendor\^(\^\fIsmc_conn\fP\^) -.br - SmcConn \fIsmc_conn\fP\^; -.FN -.eM -.PN SmcVendor -returns a string that provides some identification of the owner of -the session manager. The string should be freed with a call to -.PN free . -.sp -.LP -.sM -.FD 0 -char *SmcRelease\^(\^\fIsmc_conn\fP\^) -.br - SmcConn \fIsmc_conn\fP\^; -.FN -.eM -.PN SmcRelease -returns a string that provides the release number of the session manager. -The string should be freed with a call to -.PN free . -.sp -.LP -.sM -.FD 0 -char *SmcClientID\^(\^\fIsmc_conn\fP\^) -.br - SmcConn \fIsmc_conn\fP\^; -.FN -.eM -.PN SmcClientID -returns a null-terminated string for the client ID associated with -this connection. This information was also returned in -.PN SmcOpenConnection -(it is provided here for convenience). -Call -.PN free -on this pointer when the client ID is no longer needed. -.sp -.LP -.sM -.FD 0 -IceConn SmcGetIceConnection\^(\^\fIsmc_conn\fP\^) -.br - SmcConn \fIsmc_conn\fP\^; -.FN -.eM -.PN SmcGetIceConnection -returns the ICE connection object associated with this session management -connection object. The ICE connection object can be used to get some -additional information about the connection. Some of the more useful -functions which can be used on the IceConn are -.PN IceConnectionNumber , -.PN IceConnectionString , -.PN IceLastSentSequenceNumber , -.PN IceLastReceivedSequenceNumber , -and -.PN IcePing . -For further information, -see the \fIInter-Client Exchange Library\fP standard. -.NH 2 -Error Handling -.XS -\*(SN Error Handling -.XE -.LP -If the client receives an unexpected protocol error from the session manager, -an error handler is invoked by SMlib. A default error handler exists that -simply prints the error message to -.PN stderr -and exits if the severity of the error is fatal. -The client can change this error handler by calling the -.PN SmcSetErrorHandler -function. -.sM -.FD 0 -SmcErrorHandler SmcSetErrorHandler\^(\^\fIhandler\fP\^) -.br - SmcErrorHandler \fIhandler\fP\^; -.FN -.IP \fIhandler\fP 1i -The error handler. You should pass NULL to restore the default handler. -.LP -.eM -.PN SmcSetErrorHandler -returns the previous error handler. -.LP -The -.PN SmcErrorHandler -has the following type: -.sM -.FD 0 -typedef void (*SmcErrorHandler)(); - -void ErrorHandler\^(\^\fIsmc_conn\fP, \fIswap\fP\^, \fIoffending_minor_opcode\fP\^, \fIoffending_sequence_num\fP\^, \fIerror_class\fP\^, \fIseverity\fP\^, \fIvalues\fP\^) -.br - SmcConn \fIsmc_conn\fP\^; -.br - Bool \fIswap\fP\^; -.br - int \fIoffending_minor_opcode\fP\^; -.br - unsigned long \fIoffending_sequence_num\fP\^; -.br - int \fIerror_class\fP\^; -.br - int \fIseverity\fP\^; -.br - IcePointer \fIvalues\fP\^; -.FN -.IP \fIsmc_conn\fP 1i -The session management connection object. -.IP \fIswap\fP 1i -A flag that indicates if the specified values need byte swapping. -.IP \fIoffending_minor_opcode\fP 1i -The minor opcode of the offending message. -.IP \fIoffending_sequence_num\fP 1i -The sequence number of the offending message. -.IP \fIerror_class\fP 1i -The error class of the offending message. -.IP \fIseverity\fP 1i -.PN IceCanContinue , -.PN IceFatalToProtocol , -or -.PN IceFatalToConnection . -.IP \fIvalues\fP 1i -Any additional error values specific to the minor opcode and class. -.LP -.eM -Note that this error handler is invoked for protocol related errors. -To install an error handler to be invoked when an IO error occurs, use -.PN IceSetIOErrorHandler . -For further information, -see the \fIInter-Client Exchange Library\fP\^ standard. -.NH 1 -Session Management Server (Sms) Functions -.XS -\*(SN Session Management Server (Sms) Functions -.XE -.LP -This section discusses how Session Management servers: -.IP \(bu 5 -Initialize the library -.IP \(bu 5 -Register the client -.IP \(bu 5 -Send a ``Save Yourself'' message -.IP \(bu 5 -Send a ``Save Yourself Phase 2'' message -.IP \(bu 5 -Send an ``Interact'' message -.IP \(bu 5 -Send a ``Save Complete'' message -.IP \(bu 5 -Send a ``Die'' message -.IP \(bu 5 -Cancel a shutdown -.IP \(bu 5 -Return properties -.IP \(bu 5 -Ping a client -.IP \(bu 5 -Clean up after a client disconnects -.IP \(bu 5 -Use Sms informational functions -.IP \(bu 5 -Handle errors -.NH 2 -Initializing the Library -.XS -\*(SN Initializing the Library -.XE -.LP -.PN SmsInitialize -is the first SMlib function that should be called by a -session manager. It provides information about the session manager -and registers a callback that will be invoked each -time a new client connects to the session manager. -.sM -.FD 0 -Status SmsInitialize\^(\^\fIvendor\fP, \fIrelease\fP\^, \fInew_client_proc\fP\^, \fImanager_data\fP\^, \fIhost_based_auth_proc\fP\^, -.br - \fIerror_length\fP\^, \fIerror_string_ret\fP\^) -.br - char *\fIvendor\fP\^; -.br - char *\fIrelease\fP\^; -.br - SmsNewClientProc \fInew_client_proc\fP\^; -.br - SmPointer \fImanager_data\fP\^; -.br - IceHostBasedAuthProc \fIhost_based_auth_proc\fP\^; -.br - int \fIerror_length\fP\^; -.br - char *\fIerror_string_ret\fP\^; -.FN -.IP \fIvendor\fP 1i -A string specifying the session manager vendor. -.IP \fIrelease\fP 1i -A string specifying the session manager release number. -.IP \fInew_client_proc\fP 1i -Callback to be invoked each time a new client connects to the session manager. -.IP \fImanager_data\fP 1i -When the -.PN SmsNewClientProc -callback is invoked, this pointer to manager data will be passed. -.IP \fIhost_based_auth_proc\fP 1i -Host based authentication callback. -.IP \fIerror_length\fP 1i -Length of the error_string_ret argument passed in. -.IP \fIerror_string_ret\fP 1i -Returns a null-terminated error message, if any. -The error_string_ret points to user supplied memory. -No more than error_length bytes are used. -.LP -.eM -After the -.PN SmsInitialize -function is called, the session manager should call the -.PN IceListenForConnections -function to listen for new connections. Afterwards, each time a -client connects, the session manager should call -.PN IceAcceptConnection . -.LP -See section 9, ``Authentication of Clients,'' -for more details on authentication (including host based authentication). -Also see the \fIInter-Client Exchange Library\fP\^ standard -for further details on listening for and accepting ICE connections. -.LP -Each time a new client connects to the session manager, the -.PN SmsNewClientProc -callback is invoked. The session manager obtains a new opaque connection -object that it should use for all future interaction with the client. At -this time, the session manager must also register a set of callbacks to -respond to the different messages that the client might send. -.sM -.FD 0 -typedef Status (*SmsNewClientProc)(); - -Status NewClientProc\^(\^\fIsms_conn\fP, \fImanager_data\fP\^, \fImask_ret\fP\^, \fIcallbacks_ret\fP\^, \fIfailure_reason_ret\fP\^) -.br - SmsConn \fIsms_conn\fP\^; -.br - SmPointer \fImanager_data\fP\^; -.br - unsigned long *\fImask_ret\fP\^; -.br - SmsCallbacks *\fIcallbacks_ret\fP\^; -.br - char **\fIfailure_reason_ret\fP\^; -.FN -.IP \fIsms_conn\fP 1i -A new opaque connection object. -.IP \fImanager_data\fP 1i -Manager data specified when the callback was registered. -.IP \fImask_ret\fP 1i -On return, indicates which callbacks were set by the session manager. -.IP \fIcallbacks_ret\fP 1i -On return, contains the callbacks registered by the session manager. -.IP \fIfailure_reason_ret\fP 1i -Failure reason returned. -.LP -.eM -If a failure occurs, the -.PN SmsNewClientProc -should return a zero status as well as allocate and return a failure -reason string in failure_reason_ret. -SMlib will be responsible for freeing this memory. -.LP -The session manager must register a set of callbacks to respond to client -events. The mask_ret argument specifies which callbacks are set. -All of the callbacks specified in this version of SMlib are mandatory. The -mask_ret argument is necessary in order to maintain backwards -compatibility in future versions of the library. -.LP -The following values may be ORed together to obtain a mask value: -.LP -.Ds 0 -.PN SmsRegisterClientProcMask -.PN SmsInteractRequestProcMask -.PN SmsInteractDoneProcMask -.PN SmsSaveYourselfRequestProcMask -.PN SmsSaveYourselfP2RequestProcMask -.PN SmsSaveYourselfDoneProcMask -.PN SmsCloseConnectionProcMask -.PN SmsSetPropertiesProcMask -.PN SmsDeletePropertiesProcMask -.PN SmsGetPropertiesProcMask -.De -.LP -For each callback, the session manager can register a pointer to manager -data specific to that callback. This pointer will be passed to the callback -when it is invoked by SMlib. -.sM -.LP -.Ds 0 -.TA .5i 1i 1.5i -.ta .5i 1i 1.5i -typedef struct { - struct { - SmsRegisterClientProc callback; - SmPointer manager_data; - } register_client; - - struct { - SmsInteractRequestProc callback; - SmPointer manager_data; - } interact_request; - - struct { - SmsInteractDoneProc callback; - SmPointer manager_data; - } interact_done; - - struct { - SmsSaveYourselfRequestProc callback; - SmPointer manager_data; - } save_yourself_request; - - struct { - SmsSaveYourselfPhase2RequestProc callback; - SmPointer manager_data; - } save_yourself_phase2_request; - - struct { - SmsSaveYourselfDoneProc callback; - SmPointer manager_data; - } save_yourself_done; - - struct { - SmsCloseConnectionProc callback; - SmPointer manager_data; - } close_connection; - - struct { - SmsSetPropertiesProc callback; - SmPointer manager_data; - } set_properties; - - struct { - SmsDeletePropertiesProc callback; - SmPointer manager_data; - } delete_properties; - - struct { - SmsGetPropertiesProc callback; - SmPointer manager_data; - } get_properties; - -} SmsCallbacks; -.De -.LP -.eM -.NH 3 -The Register Client Callback -.XS -\*(SN The Register Client Callback -.XE -.LP -The Register Client callback is the first callback that will be -invoked after the client connects to the session manager. Its type is -.PN SmsRegisterClientProc . -.sM -.FD 0 -typedef Status (*SmsRegisterClientProc(); - -Status RegisterClientProc\^(\^\fIsms_conn\fP, \fImanager_data\fP\^, \fIprevious_id\fP\^) -.br - SmsConn \fIsms_conn\fP\^; -.br - SmPointer \fImanager_data\fP\^; -.br - char *\fIprevious_id\fP\^; -.FN -.IP \fIsms_conn\fP 1i -The session management connection object. -.IP \fImanager_data\fP 1i -Manager data specified when the callback was registered. -.IP \fIprevious_id\fP 1i -The client ID from the previous session. -.LP -.eM -Before any further interaction takes place with the client, -the client must be registered with the session manager. -.LP -If the client is being restarted from a previous session, -previous_id will contain a null-terminated string representing -the client ID from the previous session. Call -.PN free -on the previous_id pointer when it is no longer needed. -If the client is first joining the session, previous_id will be NULL. -.LP -If previous_id is invalid, the session manager should not register -the client at this time. This callback should return a status of zero, -which will cause an error message to be sent to the client. -The client should re-register with previous_id set to NULL. -.LP -Otherwise, the session manager should register the client with a -unique client ID by calling the -.PN SmsRegisterClientReply -function (to be discussed shortly), and the -.PN SmsRegisterClientProc -callback should return a status of one. -.NH 3 -The Interact Request Callback -.XS -\*(SN The Interact Request Callback -.XE -.LP -The Interact Request callback is of type -.PN SmsInteractRequestProc . -.sM -.FD 0 -typedef void (*SmsInteractRequestProc)(); - -void InteractRequestProc\^(\^\fIsms_conn\fP, \fImanager_data\fP\^, \fIdialog_type\fP\^) -.br - SmsConn \fIsms_conn\fP\^; -.br - SmPointer \fImanager_data\fP\^; -.br - int \fIdialog_type\fP\^; -.FN -.IP \fIsms_conn\fP 1i -The session management connection object. -.IP \fImanager_data\fP 1i -Manager data specified when the callback was registered. -.IP \fIdialog_type\fP 1i -The type of dialog the client wishes to present to the user. -.LP -.eM -When a client receives a ``Save Yourself'' message with an -interact_style of -.PN SmInteractStyleErrors -or -.PN SmInteractStyleAny , -the client may choose to interact with the user. -Because only one client can interact with the user at a time, the client -must request to interact with the user. The session manager should keep -a queue of all clients wishing to interact. It should send an ``Interact'' -message to one client at a time and wait for an ``Interact Done'' message -before continuing with the next client. -.LP -The dialog_type argument specifies either -.PN SmDialogError , -indicating that the client wants to start an error dialog, -or -.PN SmDialogNormal , -meaning that the client wishes to start a nonerror dialog. -.LP -If a shutdown is in progress, the user may have the option of cancelling -the shutdown. If the shutdown is cancelled (specified in the ``Interact -Done'' message), the session manager should send a -``Shutdown Cancelled'' message to each client that requested to interact. -.NH 3 -The Interact Done Callback -.XS -\*(SN The Interact Done Callback -.XE -.LP -When the client is done interacting with the user, the -.PN SmsInteractDoneProc -callback will be invoked. -.sM -.FD 0 -typedef void (*SmsInteractDoneProc)(); - -void InteractDoneProc\^(\^\fIsms_conn\fP, \fImanager_data\fP\^, \fIcancel_shutdown\fP\^) -.br - SmsConn \fIsms_conn\fP\^; -.br - SmPointer \fImanager_data\fP\^; -.br - Bool \fIcancel_shutdown\fP\^; -.FN -.IP \fIsms_conn\fP 1i -The session management connection object. -.IP \fImanager_data\fP 1i -Manager data specified when the callback was registered. -.IP \fIcancel_shutdown\fP 1i -Specifies if the user requests that the entire shutdown be cancelled. -.LP -.eM -Note that the shutdown can be cancelled only if the corresponding -``Save Yourself'' specified -.PN True -for shutdown and -.PN SmInteractStyleErrors -or -.PN SmInteractStyleAny -for the interact_style. -.NH 3 -The Save Yourself Request Callback -.XS -\*(SN The Save Yourself Request Callback -.XE -.LP -The Save Yourself Request callback is of type -.PN SmsSaveYourselfRequestProc . -.sM -.FD 0 -typedef void (*SmsSaveYourselfRequestProc)(); - -void SaveYourselfRequestProc\^(\^\fIsms_conn\fP, \fImanager_data\fP\^, \fIsave_type\fP\^, \fIshutdown\fP\^, \fIinteract_style\fP\^, \fIfast\fP\^, \fIglobal\fP\^) -.br - SmsConn \fIsms_conn\fP\^; -.br - SmPointer \fImanager_data\fP\^; -.br - int \fIsave_type\fP\^; -.br - Bool \fIshutdown\fP\^; -.br - int \fIinteract_style\fP\^; -.br - Bool \fIfast\fP\^; -.br - Bool \fIglobal\fP\^; -.FN -.IP \fIsms_conn\fP 1i -The session management connection object. -.IP \fImanager_data\fP 1i -Manager data specified when the callback was registered. -.IP \fIsave_type\fP 1i -Specifies the type of information that should be saved. -.IP \fIshutdown\fP 1i -Specifies if a shutdown is taking place. -.IP \fIinteract_style\fP 1i -The type of interaction allowed with the user. -.IP \fIfast\fP 1i -If -.PN True , -the client should save its state as quickly as possible. -.IP \fIglobal\fP 1i -Controls who gets the ``Save Yourself.'' -.LP -.eM -The Save Yourself Request prompts the session manager to -initiate a checkpoint or shutdown. -For information on the save_type, shutdown, interact_style, and fast arguments, -see section 6.3, ``Sending a Save Yourself Message.'' -.LP -If global is set to -.PN True , -then the resulting ``Save Yourself'' should be -sent to all applications. If global is set to -.PN False , -then the ``Save Yourself'' should only be sent to the client -that requested it. -.NH 3 -The Save Yourself Phase 2 Request Callback -.XS -\*(SN The Save Yourself Phase 2 Request Callback -.XE -.LP -The Save Yourself Phase 2 Request callback is of type -.PN SmsSaveYourselfPhase2RequestProc . -.sM -.FD 0 -typedef void (*SmsSaveYourselfPhase2RequestProc)(); - -void SmsSaveYourselfPhase2RequestProc\^(\^\fIsms_conn\fP, \fImanager_data\fP\^) -.br - SmsConn \fIsms_conn\fP\^; -.br - SmPointer \fImanager_data\fP\^; -.FN -.IP \fIsms_conn\fP 1i -The session management connection object. -.IP \fImanager_data\fP 1i -Manager data specified when the callback was registered. -.LP -.eM -This request is sent by clients that manage other clients (for example, -window managers, workspace managers, and so on). -Such managers must make sure that all of the clients that are being managed -are in an idle state so that their state can be saved. -.NH 3 -The Save Yourself Done Callback -.XS -\*(SN The Save Yourself Done Callback -.XE -.LP -When the client is done saving its state in response to a -``Save Yourself'' message, the -.PN SmsSaveYourselfDoneProc -will be invoked. -.sM -.FD 0 -typedef void (*SmsSaveYourselfDoneProc)(); - -void SaveYourselfDoneProc\^(\^\fIsms_conn\fP, \fImanager_data\fP\^, \fIsuccess\fP\^) -.br - SmsConn \fIsms_conn\fP\^; -.br - SmPointer \fImanager_data\fP\^; -.br - Bool \fIsuccess\fP\^; -.FN -.IP \fIsms_conn\fP 1i -The session management connection object. -.IP \fImanager_data\fP 1i -Manager data specified when the callback was registered. -.IP \fIsuccess\fP 1i -If -.PN True , -the Save Yourself operation was completed successfully. -.LP -.eM -Before the ``Save Yourself Done'' was sent, the client must have -set each required property at least once since it registered with the -session manager. -.NH 3 -The Connection Closed Callback -.XS -\*(SN The Connection Closed Callback -.XE -.LP -If the client properly terminates (that is, it calls -.PN SmcCloseConnection ), -the -.PN SmsCloseConnectionProc -callback is invoked. -.sM -.FD 0 -typedef void (*SmsCloseConnectionProc)(); - -void CloseConnectionProc\^(\^\fIsms_conn\fP, \fImanager_data\fP\^, \fIcount\fP\^, \fIreason_msgs\fP\^) -.br - SmsConn \fIsms_conn\fP\^; -.br - SmPointer \fImanager_data\fP\^; -.br - int \fIcount\fP\^; -.br - char **\fIreason_msgs\fP\^; -.FN -.IP \fIsms_conn\fP 1i -The session management connection object. -.IP \fImanager_data\fP 1i -Manager data specified when the callback was registered. -.IP \fIcount\fP 1i -The number of reason messages. -.IP \fIreason_msgs\fP 1i -The reasons for closing the connection. -.LP -.eM -The reason_msgs argument will most likely be NULL -and the count argument zero (0) if resignation is expected by the user. -Otherwise, it contains a list -of null-terminated Compound Text strings representing the reason for -termination. The session manager should display these reason messages -to the user. -.LP -Call -.PN SmFreeReasons -to free the reason messages. -For further information, see section 8, ``Freeing Data.'' -.NH 3 -The Set Properties Callback -.XS -\*(SN The Set Properties Callback -.XE -.LP -When the client sets session management properties, the -.PN SmsSetPropertiesProc -callback will be invoked. -.sM -.FD 0 -typedef void (*SmsSetPropertiesProc)(); - -void SetPropertiesProc\^(\^\fIsms_conn\fP, \fImanager_data\fP\^, \fInum_props\fP\^, \fIprops\fP\^) -.br - SmsConn \fIsms_conn\fP\^; -.br - SmPointer \fImanager_data\fP\^; -.br - int \fInum_props\fP\^; -.br - SmProp **\fIprops\fP\^; -.FN -.IP \fIsmc_conn\fP 1i -The session management connection object. -.IP \fImanager_data\fP 1i -Manager data specified when the callback was registered. -.IP \fInum_props\fP 1i -The number of properties. -.IP \fIprops\fP 1i -The list of properties to set. -.LP -.eM -The properties are specified as an array of property pointers. -For a description of session management properties and the -.PN SmProp -structure, see section 7, ``Session Management Properties.'' -.LP -Previously set property values may be over-written. Some properties -have predefined semantics. -The session manager is required to store -nonpredefined properties. -.LP -To free each property, use -.PN SmFreeProperty . -For further information, see section 8, ``Freeing Data.'' -You should free the actual array of pointers with a call to -.PN free . -.NH 3 -The Delete Properties Callback -.XS -\*(SN The Delete Properties Callback -.XE -.LP -When the client deletes session management properties, the -.PN SmsDeletePropertiesProc -callback will be invoked. -.sM -.FD 0 -typedef void (*SmsDeletePropertiesProc)(); - -void DeletePropertiesProc\^(\^\fIsms_conn\fP, \fImanager_data\fP\^, \fInum_props\fP\^, \fIprop_names\fP\^) -.br - SmsConn \fIsms_conn\fP\^; -.br - SmPointer \fImanager_data\fP\^; -.br - int \fInum_props\fP\^; -.br - char **\fIprop_names\fP\^; -.FN -.IP \fIsmc_conn\fP 1i -The session management connection object. -.IP \fImanager_data\fP 1i -Manager data specified when the callback was registered. -.IP \fInum_props\fP 1i -The number of properties. -.IP \fIprop_names\fP 1i -The list of properties to delete. -.LP -.eM -The properties are specified as an array of strings. -For a description of session management properties and the -.PN SmProp -structure, see section 7, ``Session Management Properties.'' -.NH 3 -The Get Properties Callback -.XS -\*(SN The Get Properties Callback -.XE -.LP -The -.PN SmsGetPropertiesProc -callback is invoked when the client wants to retrieve properties it set. -.sM -.FD 0 -typedef void (*SmsGetPropertiesProc)(); - -void GetPropertiesProc\^(\^\fIsms_conn\fP, \fImanager_data\fP\^) -.br - SmsConn \fIsms_conn\fP\^; -.br - SmPointer \fImanager_data\fP\^; -.FN -.IP \fIsmc_conn\fP 1i -The session management connection object. -.IP \fImanager_data\fP 1i -Manager data specified when the callback was registered. -.LP -.eM -The session manager should respond by calling -.PN SmsReturnProperties . -All of the properties set for this client should be returned. -.NH 2 -Registering the Client -.XS -\*(SN Registering the Client -.XE -.LP -To register a client (in response to a -.PN SmsRegisterClientProc -callback), use -.PN SmsRegisterClientReply . -.sM -.FD 0 -Status SmsRegisterClientReply\^(\^\fIsms_conn\fP, \fIclient_id\fP\^) -.br - SmsConn \fIsms_conn\fP\^; -.br - char *\fIclient_id\fP\^; -.FN -.IP \fIsms_conn\fP 1i -The session management connection object. -.IP \fIclient_id\fP 1i -A null-terminated string representing a unique client ID. -.LP -.eM -The return value of -.PN SmsRegisterClientReply -is zero for failure and a positive value for success. Failure will -occur if SMlib can not allocate memory to hold a copy of the client ID -for it's own internal needs. -.LP -If a non-NULL previous_id was specified when the client registered -itself, client_id should be identical to previous_id. -.LP -Otherwise, client_id should be a unique ID freshly generated by -the session manager. In addition, the session manager should send -a ``Save Yourself'' message with type = Local, shutdown = False, -interact-style = None, and fast = False immediately after registering the -client. -.LP -Note that once a client ID has been assigned to the client, the client keeps -this ID indefinitely. If the client is terminated and restarted, it -will be reassigned the same ID. It is desirable to be able to pass -client IDs around from machine to machine, from user to user, and -from session manager to session manager, while retaining the -identity of the client. This, combined with the indefinite -persistence of client IDs, means that client IDs need to be globally -unique. -.LP -You should call the -.PN SmsGenerateClientID -function to generate a globally unique client ID. -.sM -.FD 0 -char *SmsGenerateClientID\^(\^\fIsms_conn\fP\^) -.br - SmsConn \fIsms_conn\fP\^; -.FN -.IP \fIsms_conn\fP 1i -The session management connection object. -.LP -.eM -NULL will be returned if the ID could not be generated. Otherwise, the return -value of the function is the client ID. It should be freed with a call to -.PN free -when no longer needed. -.NH 2 -Sending a Save Yourself Message -.XS -\*(SN Sending a Save Yourself Message -.XE -.LP -To send a ``Save Yourself'' to a client, use -.PN SmsSaveYourself . -.sM -.FD 0 -void SmsSaveYourself\^(\^\fIsms_conn\fP, \fIsave_type\fP\^, \fIshutdown\fP\^, \fIinteract_style\fP\^, \fIfast\fP\^) -.br - SmsConn \fIsms_conn\fP\^; -.br - int \fIsave_type\fP\^; -.br - Bool \fIshutdown\fP\^; -.br - int \fIinteract_style\fP\^; -.br - Bool \fIfast\fP\^; -.FN -.ne 7 -.IP \fIsms_conn\fP 1i -The session management connection object. -.IP \fIsave_type\fP 1i -Specifies the type of information that should be saved. -.IP \fIshutdown\fP 1i -Specifies if a shutdown is taking place. -.IP \fIinteract_style\fP 1i -The type of interaction allowed with the user. -.IP \fIfast\fP 1i -If -.PN True , -the client should save its state as quickly as possible. -.LP -.eM -The session manager sends a ``Save Yourself'' message to a client -either to checkpoint it or just before -termination so that it can save its state. -The client responds with zero or more ``Set Properties'' messages -to update the properties indicating how to restart the client. -When all the properties have been set, the client sends a -``Save Yourself Done'' message. -.LP -If interact_style is -.PN SmInteractStyleNone , -the client must not interact with the -user while saving state. -If interact_style is -.PN SmInteractStyleErrors , -the client may interact with the user only if an error condition arises. If -interact_style is -.PN SmInteractStyleAny , -then the client may interact with the user for any purpose. -The client must send an ``Interact Request'' message -and wait for an ``Interact'' message from the session manager -before it can interact with the user. When the client is done -interacting with the user, it should send an ``Interact Done'' message. -The ``Interact Request'' message can be sent any time after a -``Save Yourself'' and before a ``Save Yourself Done.'' -.LP -If save_type is -.PN SmSaveLocal , -the client must update the properties to reflect its current state. -Specifically, it should save enough information to restore -the state as seen by the user of this client. It should not affect the -state as seen by other users. If save_type is -.PN SmSaveGlobal -the user wants the client to commit all of its data to permanent, -globally accessible storage. If save_type is -.PN SmSaveBoth , -the client should do both of these (it should first commit the data to -permanent storage before updating its properties). -.LP -The shutdown argument specifies whether the session is being -shut down. The interaction is different depending on whether or not -shutdown is set. If not shutting down, then the client can save and -resume normal operation. If shutting down, the client must save and -then must prevent interaction until it receives either a ``Die'' -or a ``Shutdown Cancelled,'' because anything the user does after -the save will be lost. -.LP -The fast argument specifies that the client should save its state -as quickly as possible. For example, if the session manager knows that -power is about to fail, it should set fast to -.PN True . -.NH 2 -Sending a Save Yourself Phase 2 Message -.XS -\*(SN Sending a Save Yourself Phase 2 Message -.XE -.LP -In order to send a ``Save Yourself Phase 2'' message to a client, use -.PN SmsSaveYourselfPhase2 . -.sM -.FD 0 -void SmsSaveYourselfPhase2\^(\^\fIsms_conn\fP\^) -.br - SmsConn \fIsms_conn\fP\^; -.FN -.IP \fIsms_conn\fP 1i -The session management connection object. -.LP -.eM -The session manager sends this message to a client that has previously sent a -``Save Yourself Phase 2 Request'' message. This message informs the -client that all other clients are in a fixed state and this client can save -state that is associated with other clients. -.NH 2 -Sending an Interact Message -.XS -\*(SN Sending an Interact Message -.XE -.LP -To send an ``Interact'' message to a client, use -.PN SmsInteract . -.sM -.FD 0 -void SmsInteract\^(\^\fIsms_conn\fP\^) -.br - SmsConn \fIsms_conn\fP\^; -.FN -.IP \fIsms_conn\fP 1i -The session management connection object. -.LP -.eM -The ``Interact'' message grants the client the privilege of interacting -with the user. When the client is done interacting with the user, it must -send an ``Interact Done'' message to the session manager. -.NH 2 -Sending a Save Complete Message -.XS -\*(SN Sending a Save Complete Message -.XE -.LP -To send a ``Save Complete'' message to a client, use -.PN SmsSaveComplete . -.sM -.FD 0 -void SmsSaveComplete\^(\^\fIsms_conn\fP\^) -.br - SmsConn \fIsms_conn\fP\^; -.FN -.IP \fIsms_conn\fP 1i -The session management connection object. -.LP -.eM -The session manager sends this message when it is done with a checkpoint. -The client is then free to change its state. -.NH 2 -Sending a Die Message -.XS -\*(SN Sending a Die Message -.XE -.LP -To send a ``Die'' message to a client, use -.PN SmsDie . -.sM -.FD 0 -void SmsDie\^(\^\fIsms_conn\fP\^) -.br - SmsConn \fIsms_conn\fP\^; -.FN -.IP \fIsms_conn\fP 1i -The session management connection object. -.LP -.eM -Before the session manager terminates, it should wait for a -``Connection Closed'' message from each client that it sent -a ``Die'' message to, timing out appropriately. -.NH 2 -Cancelling a Shutdown -.XS -\*(SN Cancelling a Shutdown -.XE -.LP -To cancel a shutdown, use -.PN SmsShutdownCancelled . -.sM -.FD 0 -void SmsShutdownCancelled\^(\^\fIsms_conn\fP\^) -.br - SmsConn \fIsms_conn\fP\^; -.FN -.IP \fIsms_conn\fP 1i -The session management connection object. -.LP -.eM -The client can now continue as if the shutdown had never happened. -If the client has not sent a ``Save Yourself Done'' message yet, it can -either abort the save and send a ``Save Yourself Done'' -with the success argument set to -.PN False , -or it can continue with the save and send a ``Save Yourself Done'' -with the success argument set to reflect the outcome of the save. -.NH 2 -Returning Properties -.XS -\*(SN Returning Properties -.XE -.LP -In response to a ``Get Properties'' message, the session manager should call -.PN SmsReturnProperties . -.sM -.FD 0 -void SmsReturnProperties\^(\^\fIsms_conn\fP\^, \fInum_props\fP\^, \fIprops\fP\^) -.br - SmsConn \fIsms_conn\fP\^; -.br - int \fInum_props\fP\^; -.br - SmProp **\fIprops\fP\^; -.FN -.IP \fIsms_conn\fP 1i -The session management connection object. -.IP \fInum_props\fP 1i -The number of properties. -.IP \fIprops\fP 1i -The list of properties to return to the client. -.LP -.eM -The properties are returned as an array of property pointers. -For a description of session management properties and the -.PN SmProp -structure, see section 7, ``Session Management Properties.'' -.NH 2 -Pinging a Client -.XS -\*(SN Pinging a Client -.XE -.LP -To check that a client is still alive, you should use the -.PN IcePing -function provided by the ICE library. -To do so, the ICE -connection must be obtained using the -.PN SmsGetIceConnection -(see section 6.12, ``Using Sms Informational Functions''). -.LP -.sM -.FD 0 -void IcePing\^(\^\fIice_conn\fP, \fIping_reply_proc\fP\^, \fIclient_data\fP\^) -.br - IceConn \fIice_conn\fP\^; -.br - IcePingReplyProc \fIping_reply_proc\fP\^; -.br - IcePointer \fIclient_data\fP\^; -.FN -.IP \fIice_conn\fP 1i -A valid ICE connection object. -.IP \fIping_reply_proc\fP 1i -The callback to invoke when the Ping reply arrives. -.IP \fIclient_data\fP 1i -This pointer will be passed to the -.PN IcePingReplyProc -callback. -.LP -.eM -When the Ping reply is ready (if ever), the -.PN IcePingReplyProc -callback will be invoked. A session manager should have some sort -of timeout period, after which it assumes the client has unexpectedly died. -.LP -.sM -.FD 0 -typedef void (*IcePingReplyProc)(); - -void PingReplyProc\^(\^\fIice_conn\fP, \fIclient_data\fP\^) -.br - IceConn \fIice_conn\fP\^; -.br - IcePointer \fIclient_data\fP\^; -.FN -.IP \fIice_conn\fP 1i -The ICE connection object. -.IP \fIclient_data\fP 1i -The client data specified in the call to -.PN IcePing . -.LP -.eM -.NH 2 -Cleaning Up After a Client Disconnects -.XS -\*(SN Cleaning Up After a Client Disconnects -.XE -.LP -When the session manager receives a ``Connection Closed'' message or -otherwise detects that the client aborted the connection, it should -call the -.PN SmsCleanUp -function in order to free up the connection object. -.sM -.FD 0 -void SmsCleanUp\^(\^\fIsms_conn\fP\^) -.br - SmsConn \fIsms_conn\fP\^; -.FN -.IP \fIsms_conn\fP 1i -The session management connection object. -.LP -.eM -.NH 2 -Using Sms Informational Functions -.XS -\*(SN Using Sms Informational Functions -.XE -.LP -.sM -.FD 0 -int SmsProtocolVersion\^(\^\fIsms_conn\fP\^) -.br - SmsConn \fIsms_conn\fP\^; -.FN -.LP -.eM -.PN SmsProtocolVersion -returns the major version of the session management protocol -associated with this session. -.sp -.LP -.sM -.FD 0 -int SmsProtocolRevision\^(\^\fIsms_conn\fP\^) -.br - SmsConn \fIsms_conn\fP\^; -.FN -.LP -.eM -.PN SmsProtocolRevision -returns the minor version of the session management protocol -associated with this session. -.sp -.LP -.sM -.FD 0 -char *SmsClientID\^(\^\fIsms_conn\fP\^) -.br - SmsConn \fIsms_conn\fP\^; -.FN -.LP -.eM -.PN SmsClientID -returns a null-terminated string for the client ID associated with -this connection. -You should call -.PN free -on this pointer when the client ID is no longer needed. -.sp -.LP -To obtain the host name of a client, use -.PN SmsClientHostName . -This host name will be needed to restart the client. -.sM -.FD 0 -char *SmsClientHostName\^(\^\fIsms_conn\fP\^) -.br - SmsConn \fIsms_conn\fP\^; -.FN -.eM -The string returned is of the form \fIprotocol\fP\^/\^\fIhostname\fP\^, -where \fIprotocol\fP\^ is one of {tcp, decnet, local}. -You should call -.PN free -on the string returned when it is no longer needed. -.sp -.LP -.sM -.FD 0 -IceConn SmsGetIceConnection\^(\^\fIsms_conn\fP\^) -.br - SmsConn \fIsms_conn\fP\^; -.FN -.eM -.PN SmsGetIceConnection -returns the ICE connection object associated with this session management -connection object. The ICE connection object can be used to get some -additional information about the connection. Some of the more useful -functions which can be used on the IceConn are -.PN IceConnectionNumber , -and -.PN IceLastSequenceNumber . -For further information, -see the \fIInter-Client Exchange Library\fP\^ standard. -.NH 2 -Error Handling -.XS -\*(SN Error Handling -.XE -.LP -If the session manager receives an unexpected protocol error from a client, -an error handler is invoked by SMlib. A default error handler exists which -simply prints the error message (it does not exit). The session manager can -change this error handler by calling -.PN SmsSetErrorHandler . -.sM -.FD 0 -SmsErrorHandler SmsSetErrorHandler\^(\^\fIhandler\fP\^) -.br - SmsErrorHandler \fIhandler\fP\^; -.FN -.IP \fIhandler\fP 1i -The error handler. -You should pass NULL to restore the default handler. -.LP -.eM -.PN SmsSetErrorHandler -returns the previous error handler. -The -.PN SmsErrorHandler -has the following type: -.sM -.FD 0 -typedef void (*SmsErrorHandler)(); - -void ErrorHandler\^(\^\fIsms_conn\fP, \fIswap\fP\^, \fIoffending_minor_opcode\fP\^, \fIoffending_sequence_num\fP\^, \fIerror_class\fP\^, \fIseverity\fP\^, \fIvalues\fP\^) -.br - SmsConn \fIsms_conn\fP\^; -.br - Bool \fIswap\fP\^; -.br - int \fIoffending_minor_opcode\fP\^; -.br - unsigned long \fIoffending_sequence_num\fP\^; -.br - int \fIerror_class\fP\^; -.br - int \fIseverity\fP\^; -.br - IcePointer \fIvalues\fP\^; -.FN -.IP \fIsms_conn\fP 1i -The session management connection object. -.IP \fIswap\fP 1i -A flag which indicates if the specified values need byte swapping. -.IP \fIoffending_minor_opcode\fP 1i -The minor opcode of the offending message. -.IP \fIoffending_sequence_num\fP 1i -The sequence number of the offending message. -.IP \fIerror_class\fP 1i -The error class of the offending message. -.IP \fIseverity\fP 1i -.PN IceCanContinue , -.PN IceFatalToProtocol , -or -.PN IceFatalToConnection . -.IP \fIvalues\fP 1i -Any additional error values specific to the minor opcode and class. -.LP -.eM -Note that this error handler is invoked for protocol related errors. -To install an error handler to be invoked when an IO error occurs, use -.PN IceSetIOErrorHandler . -For further information, -see the \fIInter-Client Exchange Library\fP\^ standard. -.NH 1 -Session Management Properties -.XS -\*(SN Session Management Properties -.XE -.LP -Each property is defined by the -.PN SmProc -structure: -.LP -.Ds 0 -.TA .5i 2.5i -.ta .5i 2.5i -typedef struct { - char *name; /* name of property */ - char *type; /* type of property */ - int num_vals; /* number of values */ - SmPropValue *vals; /* the list of values */ -} SmProp; - -typedef struct { - int length; /* the length of the value */ - SmPointer value; /* the value */ -} SmPropValue; -.De -.LP -The X Session Management Protocol defines a list of predefined properties, -several of which are required to be set by the client. The following table -specifies the predefined properties and indicates which ones are required. -Each property has a type associated with it. -.LP -A type of SmCARD8 indicates that there is a single 1-byte value. -A type of SmARRAY8 indicates that there is a single array of bytes. -A type of SmLISTofARRAY8 indicates that there is a list of array of bytes. -.LP -.TS H -l l l c . -_ -.sp 6p -.B -Name Type POSIX Type Required -.R -.sp 6p -_ -.sp 6p -.TH -SmCloneCommand OS-specific SmLISTofARRAY8 Yes -SmCurrentDirectory OS-specific SmARRAY8 No -SmDiscardCommand OS-specific SmLISTofARRAY8 No* -SmEnvironment OS-specific SmLISTofARRAY8 No -SmProcessID OS-specific SmARRAY8 No -SmProgram OS-specific SmARRAY8 Yes -SmRestartCommand OS-specific SmLISTofARRAY8 Yes -SmResignCommand OS-specific SmLISTofARRAY8 No -SmRestartStyleHint SmCARD8 SmCARD8 No -SmShutdownCommand OS-specific SmLISTofARRAY8 No -SmUserID SmARRAY8 SmARRAY8 Yes -.sp 6p -_ -.TE -.LP -* Required if any state is stored in an external repository -(for example, state file). -.IP \(bu 5 -SmCloneCommand -.IP -This is like the SmRestartCommand, -except it restarts a copy of the -application. The only difference is that the application does not -supply its client ID at register time. On POSIX systems, this should -be of type SmLISTofARRAY8. -.IP \(bu 5 -SmCurrentDirectory -.IP -On POSIX-based systems, this specifies the value of the current directory that -needs to be set up prior to starting the SmProgram and should of type SmARRAY8. -.IP \(bu 5 -SmDiscardCommand -.IP -The discard command contains a command that when delivered to the host that -the client is running on (determined from the connection), will -cause it to discard any information about the current state. If this command -is not specified, the Session Manager will assume that all of the client's -state is encoded in the SmRestartCommand. -On POSIX systems, the type should be SmLISTofARRAY8. -.IP \(bu 5 -SmEnvironment -.IP -On POSIX based systems, this will be of type SmLISTofARRAY8, -where the ARRAY8s alternate between environment variable name and environment -variable value. -.IP \(bu 5 -SmProcessID -.IP -This specifies an OS-specific identifier for the process. On POSIX -systems, this should contain the return value of -.PN getpid -turned into a Latin-1 (decimal) string. -.IP \(bu 5 -SmProgram -.IP -This is the name of the program that is running. -On POSIX systems, this should be first parameter passed to -.PN execve -and should be of type SmARRAY8. -.IP \(bu 5 -SmRestartCommand -.IP -The restart command contains a command that, when delivered to the -host that the client is running on (determined from the connection), -will cause the client to restart in -its current state. On POSIX-based systems, this is of type SmLISTofARRAY8, -and each of the elements in the array represents an element in the -.PN argv -array. -This restart command should ensure that the client restarts with the specified -client-ID. -.IP \(bu 5 -SmResignCommand -.IP -A client that sets the SmRestartStyleHint to SmRestartAnway -uses this property to specify a command -that undoes the effect of the client and removes -any saved state. -As an example, consider a user that runs -.PN xmodmap , -which registers with the Session Manager, sets SmRestartStyleHint to -SmRestartAnyway, and then terminates. To allow the Session Manager (at the -user's request) to undo this, -.PN xmodmap -would register a SmResignCommand that undoes the effects of the -.PN xmodmap . -.IP \(bu 5 -SmRestartStyleHint -.IP -If the RestartStyleHint property is present, it will contain the -style of restarting the client prefers. If this style is not specified, -SmRestartIfRunning is assumed. -The possible values are as follows: -.TS H -l n. -_ -.sp 6p -.B -Name Value -.sp 6p -_ -.sp 6p -.TH -.R -SmRestartIfRunning 0 -SmRestartAnyway 1 -SmRestartImmediately 2 -SmRestartNever 3 -.sp 6p -_ -.TE -.IP -The SmRestartIfRunning style is used in the usual case. The client should -be restarted in the next session if it was running at the end of the -current session. -.IP -The SmRestartAnyway style is used to tell the Session Manager -that the application should be restarted in the next session -even if it exits before the current session is terminated. -It should be noted that this is only -a hint and the Session Manager will follow the policies specified -by its users in determining what applications to restart. -.IP -A client that uses SmRestartAnyway should also set the -SmResignCommand and SmShutdownCommand properties to commands -that undo the state of the client after it exits. -.IP -The SmRestartImmediately style is like SmRestartAnyway, -but, in addition, the client is meant to run continuously. -If the client exits, -the Session Manager should try to restart it in the current session. -.IP -SmRestartNever style specifies that the client -does not wish to be restarted in the next session. -.IP \(bu 5 -SmShutdownCommand -.IP -This command is executed at shutdown time to clean up after a client that -is no longer running but retained its state by setting SmRestartStyleHint -to SmRestartAnyway. -The client must not remove any saved state as the client is still part of -the session. -As an example, consider a client that turns on a camera at start up time. -This client then exits. -At session shutdown, the user wants the camera turned off. -This client would set the SmRestartStyleHint to SmRestartAnyway -and would register a SmShutdownCommand that would turn off the camera. -.IP \(bu 5 -SmUserID -.IP -Specifies the user ID. On POSIX-based systems, this -will contain the user's name (the pw_name member of struct -.PN passwd ). -.NH 1 -Freeing Data -.XS -\*(SN Freeing Data -.XE -.LP -To free an individual property, use -.PN SmFreeProperty . -.sM -.FD 0 -void SmFreeProperty\^(\^\fIprop\fP\^) -.br - SmProp *\fIprop\fP\^; -.FN -.IP \fIprop\fP 1i -The property to free. -.LP -.eM -.LP -To free the reason strings from the -.PN SmsCloseConnectionProc -callback, use -.PN SmFreeReasons . -.sM -.FD 0 -void SmFreeReasons\^(\^\fIcount\fP, \fIreasons\fP\^) -.br - int \fIcount\fP\^; -.br - char **\fIreasons\fP\^; -.FN -.IP \fIcount\fP 1i -The number of reason strings. -.IP \fIreasons\fP 1i -The list of reason strings to free. -.LP -.eM -.NH 1 -Authentication of Clients -.XS -\*(SN Authentication of Clients -.XE -.LP -As stated earlier, the session management protocol is layered on top -of ICE. Authentication occurs at two levels in the ICE protocol: -.IP \(bu 5 -The first is when an ICE connection is opened. -.IP \(bu 5 -The second is when a Protocol Setup occurs on an ICE connection. -.LP -The authentication methods that are available are implementation-dependent -(that is., dependent on the ICElib and SMlib implementations in use). -For further information, -see the \fIInter-Client Exchange Library\fP\^ standard. -.NH 1 -Working in a Multi-Threaded Environment -.XS -\*(SN Working in a Multi-Threaded Environment -.XE -.LP -To declare that multiple threads in an application will be using SMlib -(or any other library layered on top of ICElib), you should call -.PN IceInitThreads . -For further information, -see the \fIInter-Client Exchange Library\fP\^ standard. -.NH 1 -Acknowledgements -.XS -\*(SN Acknowledgements -.XE -.LP -Thanks to the following people for their participation in the -X Session Management design: Jordan Brown, Ellis Cohen, -Donna Converse, Stephen Gildea, Vania Joloboff, Stuart Marks, Bob Scheifler, -Ralph Swick, and Mike Wexler. -.LP -.EH '''' -.OH '''' -.YZ 3 diff --git a/doc/SMlib.xml b/doc/SMlib.xml new file mode 100644 index 0000000..347cb14 --- /dev/null +++ b/doc/SMlib.xml @@ -0,0 +1,2359 @@ + + + + + + + + + X Session Management Library + X Consortium Standard + X Version 11, Release 6.4 + + + RalphMor + + + X Consortium Standard + 1993X Consortium + 1994X Consortium + Version 1.0 + X Consortium + X Version 11, Release 7 + + +Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: + +Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: + +The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE X CONSORTIUM BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + +Except as contained in this notice, the name of the X Consortium shall not be used in advertising or otherwise to promote the sale, use or other dealings in this Software without prior written authorization from the X Consortium. + +X Window System is a trademark of The Open Group. + + + + + +Overview of Session Management + + +The purpose of the X Session Management Protocol (XSMP) is to provide a uniform mechanism for users to save and restore their sessions. A session is a group of clients, each of which has a particular state. The session is controlled by a network service called the session manager. The session manager issues commands to its clients on behalf of the user. These commands may cause clients to save their state or to terminate. It is expected that the client will save its state in such a way that the client can be restarted at a later time and resume its operation as if it had never been terminated. A client's state might include information about the file currently being edited, the current position of the insertion point within the file, or the start of an uncommitted transaction. The means by which clients are restarted is unspecified by this protocol. + +For purposes of this protocol, a client of the session manager is defined as a connection to the session manager. A client is typically, though not necessarily, a process running an application program connected to an X display. However, a client may be connected to more than one X display or not be connected to any X displays at all. + + + + +The Session Management Library + +The Session Management Library (SMlib) is a low-level "C" language interface to XSMP. It is expected that higher level toolkits, such as Xt, will hide many of the details of session management from clients. Higher level toolkits might also be developed for session managers to use, but no such effort is currently under way. + + +SMlib has two parts to it: + + One set of functions for clients that want to be part of a session + One set of functions for session managers to call + + +Some applications will use both sets of functions and act as nested session managers. That is, they will be both a session manager and a client of another session. An example is a mail program that could start a text editor for editing the text of a mail message. The mail program is part of a regular session and, at the same time, is also acting as a session manager to the editor. + +Clients initialize by connecting to the session manager and obtaining a client-ID that uniquely identifies them in the session. The session manager maintains a list of properties for each client in the session. These properties describe the client's environment and, most importantly, describe how the client can be restarted (via an SmRestartCommand. Clients are expected to save their state in such a way as to allow multiple instantiations of themselves to be managed independently. For example, clients may use their client-ID as part of a filename in which to store the state for a particular instantiation. The client-ID should be saved as part of the SmRestartCommand so that the client will retain the same ID after it is restarted. + +Once the client initializes itself with the session manager, it must be ready to respond to messages from the session manager. For example, it might be asked to save its state or to terminate. In the case of a shutdown, the session manager might give each client a chance to interact with the user and cancel the shutdown. + + + +Understanding SMlib's Dependence on ICE + +The X Session Management Protocol is layered on top of the Inter-Client Exchange (ICE) Protocol. The ICE protocol is designed to multiplex several protocols over a single connection. As a result, working with SMlib requires a little knowledge of how the ICE library works. + +The ICE library utilizes callbacks to process messages. When a client detects that there is data to read on an ICE connection, it should call the IceProcessMessages function. IceProcessMessages will read the message header and look at the major opcode in order to determine which protocol the message was intended for. The appropriate protocol library will then be triggered to unpack the message and hand it off to the client via a callback. + +The main point to be aware of is that an application using SMlib must have some code that detects when there is data to read on an ICE connection. This can be done via a select call on the file descriptor for the ICE connection, but more typically, XtAppAddInput will be used to register a callback that will invoke IceProcessMessages each time there is data to read on the ICE connection. + +To further complicate things, knowing which file descriptors to call select on requires an understanding of how ICE connections are created. On the client side, a call must be made to SmcOpenConnection in order to open a connection with a session manager. SmcOpenConnection will internally make a call into IceOpenConnection which will, in turn, determine if an ICE connection already exists between the client and session manager. Most likely, a connection will not already exist and a new ICE connection will be created. The main point to be aware of is that, on the client side, it is not obvious when ICE connections get created or destroyed, because connections are shared when possible. To deal with this, the ICE library lets the application register watch procedures that will be invoked each time an ICE connection is opened or closed. These watch procedures could be used to add or remove ICE file descriptors from the list of descriptors to call select on. + +On the session manager side, things work a bit differently. The session manager has complete control over the creation of ICE connections. The session manager has to first call IceListenForConnections in order to start listening for connections from clients. Once a connection attempt is detected, IceAcceptConnection must be called, and the session manager can simply add the new ICE file descriptor to the list of descriptors to call select on. + +For further information on the library functions related to ICE connections, see the Inter-Client Exchange Library standard. + + + +Header Files and Library Name + +Applications (both session managers and clients) should include the header file <X11/SM/SMlib.h>. This header file defines all of the SMlib data structures and function prototypes. SMlib.h includes the header file <X11/SM/SM.h>, which defines all of the SMlib constants. + +Because SMlib is dependent on ICE, applications should link against SMlib and ICElib by using -lSM -lICE + + + +Session Management Client (Smc) Functions + + +This section discusses how Session Management clients: + + Connect to the Session Manager + Close the connection + Modify callbacks + Set, delete, and retrieve Session Manager properties + Interact with the user + Request a “Save Yourself” + Request a “Save Yourself Phase 2” + Complete a “Save Yourself” + Use Smc informational functions + Handle Errors + + + +Connecting to the Session Manager + +To open a connection with a session manager, use SmcOpenConnection + +SmcConn SmcOpenConnection(network_ids_list, context, xsmp_major_rev, xsmp_minor_rev, + +mask, callbacks, previous_id, client_id_ret, error_length, error_string_ret) + + char *network_ids_list; + SmPointer context; + int xsmp_major_rev; + int xsmp_minor_rev; + unsigned long mask; + SmcCallbacks *callbacks; + char *previous_id; + char **client_id_ret; + int error_length; + char *error_string_ret; + + +Specifies the network ID(s) of the session manager. + + + + context + A pointer to an opaque object or NULL. Used to determine if an ICE connection can be shared (see below). + + + xsmp_major_rev + The highest major version of the XSMP the application supports. + + + xsmp_minor_rev + The highest minor version of the XSMP the application supports (for the specified xsmp_major_rev). + + + mask + A mask indicating which callbacks to register. + + + callbacks + The callbacks to register. These callbacks are used to respond to messages from the session manager. + + + previous_id + The client ID from the previous session. + + + client_id_ret + The client ID for the current session is returned. + + + error_length + Length of the error_string_ret argument passed in. + + + error_string_ret + Returns a null-terminated error message, if any. The error_string_ret argument points to user supplied memory. No more than error_length bytes are used. + + + + +The network_ids_list argument is a null-terminated string containing a list of network IDs for the session manager, separated by commas. If network_ids_list is NULL, the value of the SESSION_MANAGER environment variable will be used. Each network ID has the following format: + + + + + + + + + + tcp/<hostname>:<portnumber> + or + + + + decnet/<hostname>::<objname> + or + + + + local/<hostname>:<path> + + + + + + +An attempt will be made to use the first network ID. If that fails, an attempt will be made using the second network ID, and so on. + +After the connection is established, SmcOpenConnection registers the client with the session manager. If the client is being restarted from a previous session, previous_id should contain a null terminated string representing the client ID from the previous session. If the client is first joining the session, previous_id should be set to NULL. If previous_id is specified but is determined to be invalid by the session manager, SMlib will re-register the client with previous_id set to NULL. + +If SmcOpenConnection succeeds, it returns an opaque connection pointer of type SmcConn and the client_id_ret argument contains the client ID to be used for this session. The client_id_ret should be freed with a call to free when no longer needed. On failure, SmcOpenConnection returns NULL, and the reason for failure is returned in error_string_ret. + +Note that SMlib uses the ICE protocol to establish a connection with the session manager. If an ICE connection already exists between the client and session manager, it might be possible for the same ICE connection to be used for session management. + +The context argument indicates how willing the client is to share the ICE connection with other protocols. If context is NULL, then the caller is always willing to share the connection. If context is not NULL, then the caller is not willing to use a previously opened ICE connection that has a different non-NULL context associated with it. + +As previously discussed (section 3, ``Understanding SMlib's Dependence on ICE''), the client will have to keep track of when ICE connections are created or destroyed (using IceAddConnectionWatch and IceRemoveConnectionWatch and will have to call IceProcessMessages each time a select shows that there is data to read on an ICE connection. For further information, see the Inter-Client Exchange Library standard. + +The callbacks argument contains a set of callbacks used to respond to session manager events. The mask argument specifies which callbacks are set. All of the callbacks specified in this version of SMlib are mandatory. The mask argument is necessary in order to maintain backwards compatibility in future versions of the library. + +The following values may be ORed together to obtain a mask value: + + +SmcSaveYourselfProcMask +SmcDieProcMask +SmcSaveCompleteProcMask +SmcShutdownCancelledProcMask + + +For each callback, the client can register a pointer to client data. When SMlib invokes the callback, it will pass the client data pointer. + + + + +typedef struct { + + struct { + SmcSaveYourselfProc callback; + SmPointer client_data; + } save_yourself; + + struct { + SmcDieProc callback; + SmPointer client_data; + } die; + + struct { + SmcSaveCompleteProc callback; + SmPointer client_data; + } save_complete; + + struct { + SmcShutdownCancelledProc callback; + SmPointer client_data; + } shutdown_cancelled; + +} SmcCallbacks; + + +The Save Yourself Callback + +The Save Yourself callback is of type SmcSaveYourselfProc + + + + void SaveYourselfProc + SmcConn smc_conn + SmcConn client_data + int save_type + Bool shutdown + int interact_style + Bool fast + + + + + + smc_conn + The session management connection object. + + + client_data + Client data specified when the callback was registered. + + + save_type + Specifies the type of information that should be saved. + + + shut_down + Specifies if a shutdown is taking place. + + + interact_style + The type of interaction allowed with the user. + + + fast + if True, then client should save its state as quickly as possible. + + + +The session manager sends a “Save Yourself” message to a client either to checkpoint it or just before termination so that it can save its state. The client responds with zero or more calls to SmcSetProperties to update the properties indicating how to restart the client. When all the properties have been set, the client calls SmcSaveYourselfDone + +If interact_style is SmInteractStyleNone the client must not interact with the user while saving state. If interact_style is SmInteractStyleErrors the client may interact with the user only if an error condition arises. If interact_style is SmInteractStyleAny then the client may interact with the user for any purpose. Because only one client can interact with the user at a time, the client must call SmcInteractRequest and wait for an “Interact” message from the session manager. When the client is done interacting with the user, it calls SmcInteractDone The client may only call SmcInteractRequest after it receives a “Save Yourself” message and before it calls SmcSaveYourselfDone + +If save_type is SmSaveLocal the client must update the properties to reflect its current state. Specifically, it should save enough information to restore the state as seen by the user of this client. It should not affect the state as seen by other users. If save_type is SmSaveGlobal the user wants the client to commit all of its data to permanent, globally accessible storage. If save_type is SmSaveBoth the client should do both of these (it should first commit the data to permanent storage before updating its properties). + +Some examples are as follows: + + + If a word processor were sent a “Save Yourself” with a type of SmSaveLocal it could create a temporary file that included the current contents of the file, the location of the cursor, and other aspects of the current editing session. It would then update its SmRestartCommand property with enough information to find this temporary file. + If a word processor were sent a “Save Yourself” with a type of SmSaveGlobal it would simply save the currently edited file. + If a word processor were sent a “Save Yourself” with a type of SmSaveBoth it would first save the currently edited file. It would then create a temporary file with information such as the current position of the cursor and what file is being edited. Finally, it would update its SmRestartCommand property with enough information to find the temporary file. + + +The shutdown argument specifies whether the system is being shut down. The interaction is different depending on whether or not shutdown is set. If not shutting down, the client should save its state and wait for a “Save Complete” message. If shutting down, the client must save state and then prevent interaction until it receives either a “Die” or a “Shutdown Cancelled.” + +The fast argument specifies that the client should save its state as quickly as possible. For example, if the session manager knows that power is about to fail, it would set fast to True + + + +The Die Callback + +The Die callback is of type SmcDieProc + + + + void DieProc + SmcConn smc_conn + SmcConn client_data + + + + + + smc_conn + The session management connection object. + + + client_data + Client data specified when the callback was registered. + + + + +The session manager sends a “Die” message to a client when it wants it to die. The client should respond by calling SmcCloseConnection A session manager that behaves properly will send a “Save Yourself” message before the “Die” message. + + + +The Save Complete Callback + +The Save Complete callback is of type SmcSaveCompleteProc + + + + +typedef void (*SmcSaveCompleteProc)(); + + + +void SaveCompleteProc(smc_conn, client_data) + + SmcConn smc_conn; + + SmPointer client_data; + + + + + smc_conn + The session management connection object. + + + client_data + Client data specified when the callback was registered. + + + + + + +The Shutdown Cancelled Callback + +The Shutdown Cancelled callback is of type SmcShutdownCancelledProc + + + + +typedef void (*SmcShutdownCancelledProc)(); + + + +void ShutdownCancelledProc(smc_conn, client_data) + + SmcConn smc_conn; + + SmPointer client_data; + + + + + smc_conn + The session management connection object. + + + client_data + Client data specified when the callback was registered. + + + +The session manager sends a “Shutdown Cancelled” message when the user cancelled the shutdown during an interaction (see section 5.5, “Interacting With the User”). The client can now continue as if the shutdown had never happened. If the client has not called SmcSaveYourselfDone yet, it can either abort the save and then call SmcSaveYourselfDone with the success argument set to False or it can continue with the save and then call SmcSaveYourselfDone with the success argument set to reflect the outcome of the save. + + + +Closing the Connection + +To close a connection with a session manager, use SmcCloseConnection + + +SmcCloseStatus SmcCloseConnection(smc_conn, count, reason_msgs) + + SmcConn smc_conn; + + int count; + + char **reason_msgs; + + + + smc_conn + The session management connection object. + + + count + The number of reasons for closing the connection. + + + reason_msgs + The reasons for closing the connection. + + + + +The reason_msgs argument will most likely be NULL if resignation is expected by the client. Otherwise, it contains a list of null-terminated Compound Text strings representing the reason for termination. The session manager should display these reason messages to the user. + +Note that SMlib used the ICE protocol to establish a connection with the session manager, and various protocols other than session management may be active on the ICE connection. When SmcCloseConnection is called, the ICE connection will be closed only if all protocols have been shutdown on the connection. Check the ICElib standard for IceAddConnectionWatch and IceRemoveConnectionWatch to learn how to set up a callback to be invoked each time an ICE connection is opened or closed. Typically this callback adds/removes the ICE file descriptor from the list of active descriptors to call select on (or calls XtAppAddInput or XtRemoveInput + + +SmcCloseConnection returns one of the following values: + + SmcClosedNow - the ICE connection was closed at this time, the watch procedures were invoked, and the connection was freed. + SmcClosedASAP - an IO error had occurred on the connection, but SmcCloseConnection is being called within a nested IceProcessMessages The watch procedures have been invoked at this time, but the connection will be freed as soon as possible (when the nesting level reaches zero and IceProcessMessages returns a status of IceProcessMessagesConnectionClosed + SmcConnectionInUse - the connection was not closed at this time, because it is being used by other active protocols. + + + + + +Modifying Callbacks + +To modify callbacks set up in SmcOpenConnection use SmcModifyCallbacks + + +void SmcModifyCallbacks(smc_conn, mask, callbacks) + + SmcConn smc_conn; + + unsigned long mask; + + SmcCallbacks *callbacks; + +The session management connection object. + + + smc_conn + The session management connection object. + + + mask + A mask indicating which callbacks to modify. + + + callbacks + The new callbacks. + + + +When specifying a value for the mask argument, the following values may be ORed together: + + +SmcSaveYourselfProcMask +SmcDieProcMask +SmcSaveCompleteProcMask +SmcShutdownCancelledProcMask + + + + +Setting, Deleting, and Retrieving Session Management Properties + +To set session management properties for this client, use SmcSetProperties + + +void SmcSetProperties(smc_conn, num_props, props) + + SmcConn smc_conn; + + int num_props; + + SmProp **props; + + + + + smc_conn + The session management connection object. + + + num_proprs + The number of properties. + + + props + The list of properties to set. + + + + +The properties are specified as an array of property pointers. Previously set property values may be over-written using the SmcSetProperties function. Note that the session manager is not expected to restore property values when the session is restarted. Because of this, clients should not try to use the session manager as a database for storing application specific state. + +For a description of session management properties and the SmProp structure, see section 7, “Session Management Properties.” + + +To delete properties previously set by the client, use SmcDeleteProperties + + +void SmcDeleteProperties(smc_conn, num_props, prop_names) + + SmcConn smc_conn; + + int num_props; + + char **prop_names; + + + + smc_conn + The session management connection object. + + + num_proprs + The number of properties. + + + prop_names + The list of properties to set. + + + +To get properties previously stored by the client, use SmcGetProperties + + +Status SmcGetProperties(smc_conn, prop_reply_proc, client_data) + + SmcConn smc_conn; + + SmcPropReplyProc prop_reply_proc; + + SmPointer client_data; + + + + + smc_conn + The session management connection object. + + + prop_reply_proc + The callback to be invoked when the properties reply comes back. + + + client_data + This pointer to client data will be passed to the SmcPropReplyProc callback. + + + +The return value of SmcGetProperties is zero for failure and a positive value for success. + +Note that the library does not block until the properties reply comes back. Rather, a callback of type SmcPropReplyProc is invoked when the data is ready. + + + + +typedef void (*SmcPropReplyProc)(); + + + +void PropReplyProc(smc_conn, client_data, num_props, props) + + SmcConn smc_conn; + + SmPointer client_data; + + int num_props; + + SmProp **props; + + + + + smc_conn + The session management connection object. + + + client_data + This pointer to client data will be passed to the SmcPropReplyProc callback. + + + num_props + The number of properties returned. + + + props + The list of properties returned. + + + +To free each property, use SmFreeProperty (see section 8, “Freeing Data”). To free the actual array of pointers, use free + + + +Interacting With the User + +After receiving a “Save Yourself” message with an interact_style of SmInteractStyleErrors or SmInteractStyleAny the client may choose to interact with the user. Because only one client can interact with the user at a time, the client must call SmcInteractRequest and wait for an “Interact” message from the session manager. + + +Status SmcInteractRequest(smc_conn, dialog_type, interact_proc, client_data) + + SmcConn smc_conn; + + int dialog_type; + + SmcInteractProc interact_proc; + + SmPointer client_data; + + + + + smc_conn + The session management connection object. + + + dialog_type + The type of dialog the client wishes to present to the user. + + + interact_proc + The callback to be invoked when the “Interact” message arrives from the session manager. + + + client_data + This pointer to client data will be passed to the SmcInteractProc callback when the “Interact” message arrives. + + + +The return value of SmcInteractRequest is zero for failure and a positive value for success. + +The dialog_type argument specifies either SmDialogError indicating that the client wants to start an error dialog, or SmDialogNormal meaning that the client wishes to start a nonerror dialog. + +Note that if a shutdown is in progress, the user may have the option of cancelling the shutdown. If the shutdown is cancelled, the clients that have not interacted yet with the user will receive a “Shutdown Cancelled” message instead of the “Interact” message. + +The SmcInteractProc callback will be invoked when the “Interact” message arrives from the session manager. + + + + +typedef void (*SmcInteractProc)(); + + + +void InteractProc(smc_conn, client_data) + + SmcConn smc_conn; + + SmPointer client_data; + + + + + smc_conn + The session management connection object. + + + client_data + Client data specified when the callback was registered. + + + +After interacting with the user (in response to an “Interact” message), you should call SmcInteractDone + + +void SmcInteractDone(smc_conn, cancel_shutdown) + + SmcConn smc_conn; + + Bool cancel_shutdown; + + + + + smc_conn + The session management connection object. + + + cancel_shutdown + If True, indicates that the user requests that the entire shutdown be cancelled. + + +The cancel_shutdown argument may only be True if the corresponding “Save Yourself” specified True for shutdown and SmInteractStyleErrors or SmInteractStyleAny for the interact_style. + + + +Requesting a Save Yourself + +To request a checkpoint from the session manager, use SmcRequestSaveYourself + + +void SmcRequestSaveYourself(smc_conn, save_type, shutdown, interact_style, fast, global) + + SmcConn smc_conn; + + int save_type; + + Bool shutdown; + + int interact_style; + + Bool fast; + + Bool global; + + + + + + smc_conn + The session management connection object. + + + save_type + Specifies the type of information that should be saved. + + + shutdown + Specifies if a shutdown is taking place. + + + interact_style + The type of interaction allowed with the user. + + + fast + If True the client should save its state as quickly as possible. + + + global + Controls who gets the “Save Yourself.” + + + +The save_type, shutdown, interact_style, and fast arguments are discussed in more detail in section 5.1.1, “The Save Yourself Callback.” + +If global is set to True then the resulting “Save Yourself” should be sent to all clients in the session. For example, a vendor of a Uninterruptible Power Supply (UPS) might include a Session Management client that would monitor the status of the UPS and generate a fast shutdown if the power is about to be lost. + +If global is set to False then the “Save Yourself” should only be sent to the client that requested it. + + + +Requesting a Save Yourself Phase 2 + +In response to a ``Save Yourself, the client may request to be informed when all the other clients are quiescent so that it can save their state. To do so, use SmcRequestSaveYourselfPhase2 + + +Status SmcRequestSaveYourselfPhase2(smc_conn, save_yourself_phase2_proc, client_data) + + SmcConn smc_conn; + + SmcSaveYourselfPhase2Proc save_yourself_phase2_proc; + + SmPointer client_data; + + + + + smc_conn + The session management connection object. + + + save_type_phase2_proc + The callback to be invoked when the “Save Yourself Phase 2” message arrives from the session manager. + + + client_data + This pointer to client data will be passed to the SmcSaveYourselfPhase2Proc callback when the “Save Yourself Phase 2” message arrives. + + + +The return value of SmcRequestSaveYourselfPhase2 is zero for failure and a positive value for success. + +This request is needed by clients that manage other clients (for example, window managers, workspace managers, and so on). The manager must make sure that all of the clients that are being managed are in an idle state so that their state can be saved. + + + +Completing a Save Yourself + +After saving state in response to a “Save Yourself” message, you should call SmcSaveYourselfDone + + +void SmcSaveYourselfDone(smc_conn, success) + + SmcConn smc_conn; + + Bool success; + + + + + smc_conn + The session management connection object. + + + success + If True the “Save Yourself” operation was completed successfully. + + + +Before calling SmcSaveYourselfDone the client must have set each required property at least once since the client registered with the session manager. + + + +Using Smc Informational Functions + + +int SmcProtocolVersion(smc_conn) + + SmcConn smc_conn; + + +SmcProtocolVersion returns the major version of the session management protocol associated with this session. + + + +int SmcProtocolRevision(smc_conn) + + SmcConn smc_conn; + + +SmcProtocolRevision returns the minor version of the session management protocol associated with this session. + + +char *SmcVendor(smc_conn) + + SmcConn smc_conn; + + +SmcVendor returns a string that provides some identification of the owner of the session manager. The string should be freed with a call to free + + +char *SmcRelease(smc_conn) + + SmcConn smc_conn; + + +SmcRelease returns a string that provides the release number of the session manager. The string should be freed with a call to free + + +char *SmcClientID(smc_conn) + + SmcConn smc_conn; + + +SmcClientID returns a null-terminated string for the client ID associated with this connection. This information was also returned in SmcOpenConnection (it is provided here for convenience). Call free on this pointer when the client ID is no longer needed. + + +IceConn SmcGetIceConnection(smc_conn) + + SmcConn smc_conn; + + +SmcGetIceConnection returns the ICE connection object associated with this session management connection object. The ICE connection object can be used to get some additional information about the connection. Some of the more useful functions which can be used on the IceConn are IceConnectionNumber IceConnectionString IceLastSentSequenceNumber IceLastReceivedSequenceNumber and IcePing For further information, see the Inter-Client Exchange Library standard. + + + +Error Handling + +If the client receives an unexpected protocol error from the session manager, an error handler is invoked by SMlib. A default error handler exists that simply prints the error message to stderr and exits if the severity of the error is fatal. The client can change this error handler by calling the SmcSetErrorHandler function. + + +SmcErrorHandler SmcSetErrorHandler(handler) + + SmcErrorHandler handler; + +The error handler. You should pass NULL to restore the default handler. + + +SmcSetErrorHandler returns the previous error handler. + +The SmcErrorHandler has the following type: + + + + +typedef void (*SmcErrorHandler)(); + + + +void ErrorHandler(smc_conn, swap, offending_minor_opcode, offending_sequence_num, error_class, severity, values) + + SmcConn smc_conn; + + Bool swap; + + int offending_minor_opcode; + + unsigned long offending_sequence_num; + + int error_class; + + int severity; + + IcePointer values; + + + + + smc_conn + The session management connection object. + + + swap + A flag that indicates if the specified values need byte swapping. + + + offending_minor_opcode + The minor opcode of the offending message. + + + offending_sequence_num + The sequence number of the offending message. + + + error_class + The error class of the offending message. + + + severity + IceCanContinueIceFatalToProtocol or IceFatalToConnection + + + values + Any additional error values specific to the minor opcode and class. + + + +Note that this error handler is invoked for protocol related errors. To install an error handler to be invoked when an IO error occurs, use IceSetIOErrorHandler For further information, see the Inter-Client Exchange Library standard. + + + + +Session Management Server (Sms) Functions + +This section discusses how Session Management servers: + + + Initialize the library + Register the client + Send a “Save Yourself” message + Send a “Save Yourself Phase 2” message + Send an “Interact” message + Send a “Save Complete” message + Send a “Die” message + Cancel a shutdown + Return properties + Ping a client + Clean up after a client disconnects + Use Sms informational functions + Handle errors + + + +Initializing the Library + +SmsInitialize is the first SMlib function that should be called by a session manager. It provides information about the session manager and registers a callback that will be invoked each time a new client connects to the session manager. + + +Status SmsInitialize(vendor, release, new_client_proc, manager_data, host_based_auth_proc, + + error_length, error_string_ret) + + char *vendor; + + char *release; + + SmsNewClientProc new_client_proc; + + SmPointer manager_data; + + IceHostBasedAuthProc host_based_auth_proc; + + int error_length; + + char *error_string_ret; + + + + + + + vendor + A string specifying the session manager vendor. + + + release + A string specifying the session manager release number. + + + new_client_proc + Callback to be invoked each time a new client connects to the session manager. + + + manager_data + When the SmsNewClientProc callback is invoked, this pointer to manager data will be passed. + + + host_based_auth_proc + Host based authentication callback. + + + error_length + Length of the error_string_ret argument passed in. + + + error_string_ret + Returns a null-terminated error message, if any. The error_string_ret points to user supplied memory. No more than error_length bytes are used. + + + +After the SmsInitialize function is called, the session manager should call the IceListenForConnections function to listen for new connections. Afterwards, each time a client connects, the session manager should call IceAcceptConnection + +See section 9, “Authentication of Clients,” for more details on authentication (including host based authentication). Also see the Inter-Client Exchange Library standard for further details on listening for and accepting ICE connections. + +Each time a new client connects to the session manager, the SmsNewClientProc callback is invoked. The session manager obtains a new opaque connection object that it should use for all future interaction with the client. At this time, the session manager must also register a set of callbacks to respond to the different messages that the client might send. + + + + +typedef Status (*SmsNewClientProc)(); + + + +Status NewClientProc(sms_conn, manager_data, mask_ret, callbacks_ret, failure_reason_ret) + + SmsConn sms_conn; + + SmPointer manager_data; + + unsigned long *mask_ret; + + SmsCallbacks *callbacks_ret; + + char **failure_reason_ret; + + + + + sms_conn + A new opaque connection object. + + + manager_data + Manager data specified when the callback was registered. + + + mask_ret + On return, indicates which callbacks were set by the session manager. + + + callbacks_ret + On return, contains the callbacks registered by the session manager. + + + failure_reason_ret + Failure reason returned. + + + +If a failure occurs, the SmsNewClientProc should return a zero status as well as allocate and return a failure reason string in failure_reason_ret. SMlib will be responsible for freeing this memory. + +The session manager must register a set of callbacks to respond to client events. The mask_ret argument specifies which callbacks are set. All of the callbacks specified in this version of SMlib are mandatory. The mask_ret argument is necessary in order to maintain backwards compatibility in future versions of the library. + +The following values may be ORed together to obtain a mask value: + + +SmsRegisterClientProcMask +SmsInteractRequestProcMask +SmsInteractDoneProcMask +SmsSaveYourselfRequestProcMask +SmsSaveYourselfP2RequestProcMask +SmsSaveYourselfDoneProcMask +SmsCloseConnectionProcMask +SmsSetPropertiesProcMask +SmsDeletePropertiesProcMask +SmsGetPropertiesProcMask + + +For each callback, the session manager can register a pointer to manager data specific to that callback. This pointer will be passed to the callback when it is invoked by SMlib. + + +typedef struct { + struct { + SmsRegisterClientProc callback; + SmPointer manager_data; + } register_client; + + struct { + SmsInteractRequestProc callback; + SmPointer manager_data; + } interact_request; + + struct { + SmsInteractDoneProc callback; + SmPointer manager_data; + } interact_done; + + struct { + SmsSaveYourselfRequestProc callback; + SmPointer manager_data; + } save_yourself_request; + + struct { + SmsSaveYourselfPhase2RequestProc callback; + SmPointer manager_data; + } save_yourself_phase2_request; + + struct { + SmsSaveYourselfDoneProc callback; + SmPointer manager_data; + } save_yourself_done; + + struct { + SmsCloseConnectionProc callback; + SmPointer manager_data; + } close_connection; + + struct { + SmsSetPropertiesProc callback; + SmPointer manager_data; + } set_properties; + + struct { + SmsDeletePropertiesProc callback; + SmPointer manager_data; + } delete_properties; + + struct { + SmsGetPropertiesProc callback; + SmPointer manager_data; + } get_properties; + +} SmsCallbacks; + + + +The Register Client Callback + +The Register Client callback is the first callback that will be invoked after the client connects to the session manager. Its type is SmsRegisterClientProc + + + + +typedef Status (*SmsRegisterClientProc(); + + + +Status RegisterClientProc(sms_conn, manager_data, previous_id) + + SmsConn sms_conn; + + SmPointer manager_data; + + char *previous_id; + + + + + sms_conn + The session management connection object. + + + manager_data + Manager data specified when the callback was registered. + + + previous_id + The client ID from the previous session. + + + +Before any further interaction takes place with the client, the client must be registered with the session manager. + +If the client is being restarted from a previous session, previous_id will contain a null-terminated string representing the client ID from the previous session. Call free on the previous_id pointer when it is no longer needed. +If the client is first joining the session, previous_id will be NULL. + +If previous_id is invalid, the session manager should not register the client at this time. This callback should return a status of zero, which will cause an error message to be sent to the client. The client should re-register with previous_id set to NULL. + +Otherwise, the session manager should register the client with a unique client ID by calling the SmsRegisterClientReply function (to be discussed shortly), and the SmsRegisterClientProc callback should return a status of one. + + + +The Interact Request Callback + +The Interact Request callback is of type SmsInteractRequestProc + + + + +typedef void (*SmsInteractRequestProc)(); + + + +void InteractRequestProc(sms_conn, manager_data, dialog_type) + + SmsConn sms_conn; + + SmPointer manager_data; + + int dialog_type; + + + + + sms_conn + The session management connection object. + + + manager_data + Manager data specified when the callback was registered. + + + dialog_type + The type of dialog the client wishes to present to the user. + + + +When a client receives a “Save Yourself” message with an interact_style of SmInteractStyleErrors or SmInteractStyleAny the client may choose to interact with the user. Because only one client can interact with the user at a time, the client must request to interact with the user. The session manager should keep a queue of all clients wishing to interact. It should send an “Interact” message to one client at a time and wait for an “Interact Done” message before continuing with the next client. + +The dialog_type argument specifies either SmDialogError indicating that the client wants to start an error dialog, or SmDialogNormal meaning that the client wishes to start a nonerror dialog. + +If a shutdown is in progress, the user may have the option of cancelling the shutdown. If the shutdown is cancelled (specified in the “Interact Done” message), the session manager should send a “Shutdown Cancelled” message to each client that requested to interact. + + + +The Interact Done Callback + +When the client is done interacting with the user, the SmsInteractDoneProc callback will be invoked. + + + + +typedef void (*SmsInteractDoneProc)(); + + + +void InteractDoneProc(sms_conn, manager_data, cancel_shutdown) + + SmsConn sms_conn; + + SmPointer manager_data; + + Bool cancel_shutdown; + + + + + sms_conn + The session management connection object. + + + manager_data + Manager data specified when the callback was registered. + + + cancel_shutdown + Specifies if the user requests that the entire shutdown be cancelled. + + + +Note that the shutdown can be cancelled only if the corresponding “Save Yourself” specified True for shutdown and SmInteractStyleErrors or SmInteractStyleAny for the interact_style. + + + + + + +The Save Yourself Request Callback + +The Save Yourself Request callback is of type SmsSaveYourselfRequestProc + + + + +typedef void (*SmsSaveYourselfRequestProc)(); + + + +void SaveYourselfRequestProc(sms_conn, manager_data, save_type, shutdown, interact_style, fast, global) + + SmsConn sms_conn; + + SmPointer manager_data; + + int save_type; + + Bool shutdown; + + int interact_style; + + Bool fast; + + Bool global; + + + + + sms_conn + The session management connection object. + + + manager_data + Manager data specified when the callback was registered. + + + save_type + Specifies the type of information that should be saved. + + + shutdown + Specifies if a shutdown is taking place. + + + interact_style + The type of interaction allowed with the user. + + + fast + If True the client should save its state as quickly as possible. + + + global + Controls who gets the “Save Yourself.” + + + +The Save Yourself Request prompts the session manager to initiate a checkpoint or shutdown. For information on the save_type, shutdown, interact_style, and fast arguments, see section 6.3, “Sending a Save Yourself Message.” + +If global is set to True then the resulting “Save Yourself” should be sent to all applications. If global is set to False then the “Save Yourself” should only be sent to the client that requested it. + + + +The Save Yourself Phase 2 Request Callback + +The Save Yourself Phase 2 Request callback is of type SmsSaveYourselfPhase2RequestProc + + + + +typedef void (*SmsSaveYourselfPhase2RequestProc)(); + + + +void SmsSaveYourselfPhase2RequestProc(sms_conn, manager_data) + + SmsConn sms_conn; + + SmPointer manager_data; + + + + + sms_conn + The session management connection object. + + + manager_data + Manager data specified when the callback was registered. + + + +This request is sent by clients that manage other clients (for example, window managers, workspace managers, and so on). Such managers must make sure that all of the clients that are being managed are in an idle state so that their state can be saved. + + + +The Save Yourself Done Callback + +When the client is done saving its state in response to a “Save Yourself” message, the SmsSaveYourselfDoneProc will be invoked. + + + + +typedef void (*SmsSaveYourselfDoneProc)(); + + + +void SaveYourselfDoneProc(sms_conn, manager_data, success) + + SmsConn sms_conn; + + SmPointer manager_data; + + Bool success; + + + + + sms_conn + The session management connection object. + + + manager_data + Manager data specified when the callback was registered. + + + success + If True the Save Yourself operation was completed successfully. + + + +Before the “Save Yourself Done” was sent, the client must have set each required property at least once since it registered with the session manager. + + + +The Connection Closed Callback + +If the client properly terminates (that is, it calls SmcCloseConnection the SmsCloseConnectionProc callback is invoked. + + + + +typedef void (*SmsCloseConnectionProc)(); + + + +void CloseConnectionProc(sms_conn, manager_data, count, reason_msgs) + + SmsConn sms_conn; + + SmPointer manager_data; + + int count; + + char **reason_msgs; + + + + sms_conn + The session management connection object. + + + manager_data + Manager data specified when the callback was registered. + + + count + The number of reason messages. + + + reason_msgs + The reasons for closing the connection. + + + +The reason_msgs argument will most likely be NULL and the count argument zero (0) if resignation is expected by the user. Otherwise, it contains a list of null-terminated Compound Text strings representing the reason for termination. The session manager should display these reason messages to the user. + +Call SmFreeReasons to free the reason messages. For further information, see section 8, “Freeing Data.” + + + +The Set Properties Callback + +When the client sets session management properties, the SmsSetPropertiesProc callback will be invoked. + + + + +typedef void (*SmsSetPropertiesProc)(); + + + +void SetPropertiesProc(sms_conn, manager_data, num_props, props) + + SmsConn sms_conn; + + SmPointer manager_data; + + int num_props; + + SmProp **props; + + + + sms_conn + The session management connection object. + + + manager_data + Manager data specified when the callback was registered. + + + num_props + The number of properties. + + + props + The list of properties to set. + + + +The properties are specified as an array of property pointers. For a description of session management properties and the SmProp structure, see section 7, “Session Management Properties.” + +Previously set property values may be over-written. Some properties have predefined semantics. The session manager is required to store nonpredefined properties. + +To free each property, use SmFreeProperty For further information, see section 8, “Freeing Data.” You should free the actual array of pointers with a call to free + + + +The Delete Properties Callback + +When the client deletes session management properties, the SmsDeletePropertiesProc callback will be invoked. + + + + +typedef void (*SmsDeletePropertiesProc)(); + + + +void DeletePropertiesProc(sms_conn, manager_data, num_props, prop_names) + + SmsConn sms_conn; + + SmPointer manager_data; + + int num_props; + + char **prop_names; + + + + + sms_conn + The session management connection object. + + + manager_data + Manager data specified when the callback was registered. + + + num_props + The number of properties. + + + prop_names + The list of properties to delete. + + + +The properties are specified as an array of strings. For a description of session management properties and the SmProp structure, see section 7, “Session Management Properties.” + + + +The Get Properties Callback + +The SmsGetPropertiesProc callback is invoked when the client wants to retrieve properties it set. + + + + +typedef void (*SmsGetPropertiesProc)(); + + + +void GetPropertiesProc(sms_conn, manager_data) + + SmsConn sms_conn; + + SmPointer manager_data; + + + + + sms_conn + The session management connection object. + + + manager_data + Manager data specified when the callback was registered. + + + +The session manager should respond by calling SmsReturnProperties All of the properties set for this client should be returned. + + + +Registering the Client + +To register a client (in response to a SmsRegisterClientProc callback), use SmsRegisterClientReply + + +Status SmsRegisterClientReply(sms_conn, client_id) + + SmsConn sms_conn; + + char *client_id; + + + + + sms_conn + The session management connection object. + + + client_id + A null-terminated string representing a unique client ID. + + + +The return value of SmsRegisterClientReply is zero for failure and a positive value for success. Failure will occur if SMlib can not allocate memory to hold a copy of the client ID for it's own internal needs. + +If a non-NULL previous_id was specified when the client registered itself, client_id should be identical to previous_id. + +Otherwise, client_id should be a unique ID freshly generated by the session manager. In addition, the session manager should send a “Save Yourself” message with type = Local, shutdown = False, interact-style = None, and fast = False immediately after registering the client. + +Note that once a client ID has been assigned to the client, the client keeps this ID indefinitely. If the client is terminated and restarted, it will be reassigned the same ID. It is desirable to be able to pass client IDs around from machine to machine, from user to user, and from session manager to session manager, while retaining the identity of the client. This, combined with the indefinite persistence of client IDs, means that client IDs need to be globally unique. + +You should call the SmsGenerateClientID function to generate a globally unique client ID. + + +char *SmsGenerateClientID(sms_conn) + + SmsConn sms_conn; + + + + + sms_conn + The session management connection object. + + + + +NULL will be returned if the ID could not be generated. Otherwise, the return value of the function is the client ID. It should be freed with a call to free when no longer needed. + + + +Sending a Save Yourself Message + +To send a “Save Yourself” to a client, use SmsSaveYourself + + +void SmsSaveYourself(sms_conn, save_type, shutdown, interact_style, fast) + + SmsConn sms_conn; + + int save_type; + + Bool shutdown; + + int interact_style; + + Bool fast; + + + + sms_conn + The session management connection object. + + + save_type + Specifies the type of information that should be saved. + + + shutdown + Specifies if a shutdown is taking place. + + + interact_style + The type of interaction allowed with the user. + + + fast + If True the client should save its state as quickly as possible. + + + + +The session manager sends a “Save Yourself” message to a client either to checkpoint it or just before termination so that it can save its state. The client responds with zero or more “Set Properties” messages to update the properties indicating how to restart the client. When all the properties have been set, the client sends a “Save Yourself Done” message. + +If interact_style is SmInteractStyleNone the client must not interact with the user while saving state. If interact_style is SmInteractStyleErrors the client may interact with the user only if an error condition arises. If interact_style is SmInteractStyleAny then the client may interact with the user for any purpose. The client must send an “Interact Request” message and wait for an “Interact” message from the session manager before it can interact with the user. When the client is done interacting with the user, it should send an “Interact Done” message. The “Interact Request” message can be sent any time after a “Save Yourself” and before a “Save Yourself Done.” + +If save_type is SmSaveLocal the client must update the properties to reflect its current state. Specifically, it should save enough information to restore the state as seen by the user of this client. It should not affect the state as seen by other users. If save_type is SmSaveGlobal the user wants the client to commit all of its data to permanent, globally accessible storage. If save_type is SmSaveBoth the client should do both of these (it should first commit the data to permanent storage before updating its properties). + +The shutdown argument specifies whether the session is being shut down. The interaction is different depending on whether or not shutdown is set. If not shutting down, then the client can save and resume normal operation. If shutting down, the client must save and then must prevent interaction until it receives either a “Die” or a “Shutdown Cancelled,” because anything the user does after the save will be lost. + +The fast argument specifies that the client should save its state as quickly as possible. For example, if the session manager knows that power is about to fail, it should set fast to True + + + +Sending a Save Yourself Phase 2 Message + +In order to send a “Save Yourself Phase 2” message to a client, use SmsSaveYourselfPhase2 + + +void SmsSaveYourselfPhase2(sms_conn) + + SmsConn sms_conn; + + + + + sms_conn + The session management connection object. + + + +The session manager sends this message to a client that has previously sent a “Save Yourself Phase 2 Request” message. This message informs the client that all other clients are in a fixed state and this client can save state that is associated with other clients. + + + +Sending an Interact Message + +To send an “Interact” message to a client, use SmsInteract + + +void SmsInteract(sms_conn) + + SmsConn sms_conn; + + + + + sms_conn + The session management connection object. + + + +The “Interact” message grants the client the privilege of interacting with the user. When the client is done interacting with the user, it must send an “Interact Done” message to the session manager. + + + + + +Sending a Save Complete Message + +To send a “Save Complete” message to a client, use SmsSaveComplete + + +void SmsSaveComplete(sms_conn) + + SmsConn sms_conn; + + + + + sms_conn + The session management connection object. + + + +The session manager sends this message when it is done with a checkpoint. The client is then free to change its state. + + + +Sending a Die Message + +To send a “Die” message to a client, use SmsDie + + +void SmsDie(sms_conn) + + SmsConn sms_conn; + + + + + sms_conn + The session management connection object. + + + +Before the session manager terminates, it should wait for a “Connection Closed” message from each client that it sent a “Die” message to, timing out appropriately. + + + +Cancelling a Shutdown + +To cancel a shutdown, use SmsShutdownCancelled + + +void SmsShutdownCancelled(sms_conn) + + SmsConn sms_conn; + + + + + sms_conn + The session management connection object. + + + +The client can now continue as if the shutdown had never happened. If the client has not sent a “Save Yourself Done” message yet, it can either abort the save and send a “Save Yourself Done” with the success argument set to False or it can continue with the save and send a “Save Yourself Done” with the success argument set to reflect the outcome of the save. + + + + +Returning Properties + +In response to a “Get Properties” message, the session manager should call SmsReturnProperties + + +void SmsReturnProperties(sms_conn, num_props, props) + + SmsConn sms_conn; + + int num_props; + + SmProp **props; + + + + + sms_conn + The session management connection object. + + + num_props + The number of properties. + + + props + The list of properties to return to the client. + + + +The properties are returned as an array of property pointers. For a description of session management properties and the SmProp structure, see section 7, “Session Management Properties.” + + + +Pinging a Client + +To check that a client is still alive, you should use the IcePing function provided by the ICE library. To do so, the ICE connection must be obtained using the SmsGetIceConnection (see section 6.12, “Using Sms Informational Functions”). + + + +void IcePing(ice_conn, ping_reply_proc, client_data) + + IceConn ice_conn; + + IcePingReplyProc ping_reply_proc; + + IcePointer client_data; + + + + + ice_conn + A valid ICE connection object. + + + ping_reply_proc + The callback to invoke when the Ping reply arrives. + + + client_data + This pointer will be passed to the IcePingReplyProc callback. + + + + +When the Ping reply is ready (if ever), the IcePingReplyProc callback will be invoked. A session manager should have some sort of timeout period, after which it assumes the client has unexpectedly died. + + + + +typedef void (*IcePingReplyProc)(); + + + +void PingReplyProc(ice_conn, client_data) + + IceConn ice_conn; + + IcePointer client_data; + + + + + ice_conn + A valid ICE connection object. + + + client_data + The client data specified in the call to IcePing + + + + + +Cleaning Up After a Client Disconnects + +When the session manager receives a “Connection Closed” message or otherwise detects that the client aborted the connection, it should call the SmsCleanUp function in order to free up the connection object. + + +void SmsCleanUp(sms_conn) + + SmsConn sms_conn; + + + + + sms_conn + The session management connection object. + + + + + + +Using Sms Informational Functions + + +int SmsProtocolVersion(sms_conn) + + SmsConn sms_conn; + + +SmsProtocolVersion returns the major version of the session management protocol associated with this session. + + +int SmsProtocolRevision(sms_conn) + + SmsConn sms_conn; + + +SmsProtocolRevision returns the minor version of the session management protocol associated with this session. + + +char *SmsClientID(sms_conn) + + SmsConn sms_conn; + + +SmsClientID returns a null-terminated string for the client ID associated with this connection. You should call free on this pointer when the client ID is no longer needed. + + +To obtain the host name of a client, use SmsClientHostName This host name will be needed to restart the client. + + +char *SmsClientHostName(sms_conn) + + SmsConn sms_conn; + + +The string returned is of the form protocol/hostname, where protocol is one of {tcp, decnet, local}. You should call free on the string returned when it is no longer needed. + + +IceConn SmsGetIceConnection(sms_conn) + + SmsConn sms_conn; + + +SmsGetIceConnection returns the ICE connection object associated with this session management connection object. The ICE connection object can be used to get some additional information about the connection. Some of the more useful functions which can be used on the IceConn are IceConnectionNumber and IceLastSequenceNumber For further information, see the Inter-Client Exchange Library standard. + + + +Error Handling + +If the session manager receives an unexpected protocol error from a client, an error handler is invoked by SMlib. A default error handler exists which simply prints the error message (it does not exit). The session manager can change this error handler by calling SmsSetErrorHandler + + +SmsErrorHandler SmsSetErrorHandler(handler) + + SmsErrorHandler handler; + +The error handler. You should pass NULL to restore the default handler. + +SmsSetErrorHandler returns the previous error handler. The SmsErrorHandler has the following type: + + + + +typedef void (*SmsErrorHandler)(); + + + +void ErrorHandler(sms_conn, swap, offending_minor_opcode, offending_sequence_num, error_class, severity, values) + + SmsConn sms_conn; + + Bool swap; + + int offending_minor_opcode; + + unsigned long offending_sequence_num; + + int error_class; + + int severity; + + IcePointer values; + + + + + sms_conn + The session management connection object. + + + swap + A flag which indicates if the specified values need byte swapping. + + + offending_minor_opcode + The minor opcode of the offending message. + + + offending_sequence_num + The sequence number of the offending message. + + + error_class + The error class of the offending message. + + + severity + IceCanContinueIceFatalToProtocol or IceFatalToConnection + + + values + Any additional error values specific to the minor opcode and class. + + + +Note that this error handler is invoked for protocol related errors. To install an error handler to be invoked when an IO error occurs, use IceSetIOErrorHandler For further information, see the Inter-Client Exchange Library standard. + + + + +Session Management Properties + +Each property is defined by the SmProc structure: + + +typedef struct { + char *name; /* name of property */ + char *type; /* type of property */ + int num_vals; /* number of values */ + SmPropValue *vals; /* the list of values */ +} SmProp; + +typedef struct { + int length; /* the length of the value */ + SmPointer value; /* the value */ +} SmPropValue; + + +The X Session Management Protocol defines a list of predefined properties, several of which are required to be set by the client. The following table specifies the predefined properties and indicates which ones are required. Each property has a type associated with it. + +A type of SmCARD8 indicates that there is a single 1-byte value. A type of SmARRAY8 indicates that there is a single array of bytes. A type of SmLISTofARRAY8 indicates that there is a list of array of bytes. + + + + + + + + + + .sp 6p + + + + + + .B + + + + + + Name + Type + POSIX Type + Required + + + .R + + + + + + .sp 6p + + + + + + .sp 6p + + + + + + .TH + + + + + + + + SmCloneCommand + OS-specific + SmLISTofARRAY8 + Yes + + + SmCurrentDirectory + OS-specific + SmARRAY8 + No + + + SmDiscardCommand + OS-specific + SmLISTofARRAY8 + No* + + + SmEnvironment + OS-specific + SmLISTofARRAY8 + No + + + SmProcessID + OS-specific + SmARRAY8 + No + + + SmProgram + OS-specific + SmARRAY8 + Yes + + + SmRestartCommand + OS-specific + SmLISTofARRAY8 + Yes + + + SmResignCommand + OS-specific + SmLISTofARRAY8 + No + + + SmRestartStyleHint + SmCARD8 + SmCARD8 + No + + + SmShutdownCommand + OS-specific + SmLISTofARRAY8 + No + + + SmUserID + SmARRAY8 + SmARRAY8 + Yes + + + .sp 6p + + + + + + + + +* Required if any state is stored in an external repository (for example, state file). + + + SmCloneCommandThis is like the SmRestartCommand, except it restarts a copy of the application. The only difference is that the application does not supply its client ID at register time. On POSIX systems, this should be of type SmLISTofARRAY8. + SmCurrentDirectoryOn POSIX-based systems, this specifies the value of the current directory that needs to be set up prior to starting the SmProgram and should of type SmARRAY8. + SmDiscardCommandThe discard command contains a command that when delivered to the host that the client is running on (determined from the connection), will cause it to discard any information about the current state. If this command is not specified, the Session Manager will assume that all of the client's state is encoded in the SmRestartCommand. On POSIX systems, the type should be SmLISTofARRAY8. + SmEnvironment On POSIX based systems, this will be of type SmLISTofARRAY8, where the ARRAY8s alternate between environment variable name and environment variable value. + SmProcessIDThis specifies an OS-specific identifier for the process. On POSIX systems, this should contain the return value of getpid turned into a Latin-1 (decimal) string. + SmProgramThis is the name of the program that is running. On POSIX systems, this should be first parameter passed to execve and should be of type SmARRAY8. + SmRestartCommandThe restart command contains a command that, when delivered to the host that the client is running on (determined from the connection), will cause the client to restart in its current state. On POSIX-based systems, this is of type SmLISTofARRAY8, and each of the elements in the array represents an element in the argv array. This restart command should ensure that the client restarts with the specified client-ID. + SmResignCommandA client that sets the SmRestartStyleHint to SmRestartAnway uses this property to specify a command that undoes the effect of the client and removes any saved state. As an example, consider a user that runs xmodmap which registers with the Session Manager, sets SmRestartStyleHint to SmRestartAnyway, and then terminates. To allow the Session Manager (at the user's request) to undo this, xmodmap would register a SmResignCommand that undoes the effects of the xmodmap + SmRestartStyleHintIf the RestartStyleHint property is present, it will contain the style of restarting the client prefers. If this style is not specified, SmRestartIfRunning is assumed. The possible values are as follows: + + + + + + + + .sp 6p + + + + .B + + + + Name + Value + + + .sp 6p + + + + .sp 6p + + + + .TH + + + + + + .R + + + + SmRestartIfRunning + 0 + + + SmRestartAnyway + 1 + + + SmRestartImmediately + 2 + + + SmRestartNever + 3 + + + .sp 6p + + + + + + +The SmRestartIfRunning style is used in the usual case. The client should be restarted in the next session if it was running at the end of the current session. + +The SmRestartAnyway style is used to tell the Session Manager that the application should be restarted in the next session even if it exits before the current session is terminated. It should be noted that this is only a hint and the Session Manager will follow the policies specified by its users in determining what applications to restart. + +A client that uses SmRestartAnyway should also set the SmResignCommand and SmShutdownCommand properties to commands that undo the state of the client after it exits. + +The SmRestartImmediately style is like SmRestartAnyway, but, in addition, the client is meant to run continuously. If the client exits, the Session Manager should try to restart it in the current session. + +SmRestartNever style specifies that the client does not wish to be restarted in the next session. + + SmShutdownCommandThis command is executed at shutdown time to clean up after a client that is no longer running but retained its state by setting SmRestartStyleHint to SmRestartAnyway. The client must not remove any saved state as the client is still part of the session. As an example, consider a client that turns on a camera at start up time. This client then exits. At session shutdown, the user wants the camera turned off. This client would set the SmRestartStyleHint to SmRestartAnyway and would register a SmShutdownCommand that would turn off the camera. + SmUserIDSpecifies the user ID. On POSIX-based systems, this will contain the user's name (the pw_name member of struct passwd + + + + +Freeing Data + +To free an individual property, use SmFreeProperty + + +void SmFreeProperty(prop) + + SmProp *prop; + + + + + prop + The property to free. + + + +To free the reason strings from the SmsCloseConnectionProc callback, use SmFreeReasons + + +void SmFreeReasons(count, reasons) + + int count; + + char **reasons; + + + + + + count + The number of reason strings. + + + reasons + The list of reason strings to free. + + + + + +Authentication of Clients + +As stated earlier, the session management protocol is layered on top of ICE. Authentication occurs at two levels in the ICE protocol: + + + The first is when an ICE connection is opened. + The second is when a Protocol Setup occurs on an ICE connection. + + +The authentication methods that are available are implementation-dependent +(that is., dependent on the ICElib and SMlib implementations in use). For further information, see the Inter-Client Exchange Library standard. + + + +Working in a Multi-Threaded Environment + +To declare that multiple threads in an application will be using SMlib (or any other library layered on top of ICElib), you should call IceInitThreads For further information, see the Inter-Client Exchange Library standard. + + + +Acknowledgements + +Thanks to the following people for their participation in the X Session Management design: Jordan Brown, Ellis Cohen, Donna Converse, Stephen Gildea, Vania Joloboff, Stuart Marks, Bob Scheifler, Ralph Swick, and Mike Wexler. + + + diff --git a/doc/macros.t b/doc/macros.t deleted file mode 100644 index cbc599b..0000000 --- a/doc/macros.t +++ /dev/null @@ -1,226 +0,0 @@ -.\" $Xorg: macros.t,v 1.3 2000/08/17 19:42:51 cpqbld Exp $ -.\" macros.t -- macros for X Consortium documents -.\" Revised and commented by smarks 93.12.20. -.\" -.\" global setup: set ragged right, assign string variables -.\" -.na -.ie n \{\ -.ds Q \&" -.ds U \&" -.ds - \%-- -.\} -.el \{\ -.ds Q `\h'-\w'\^'u'` -.ds U '\h'-\w'\^'u'' -.ds - \(em -.\} -.\" -.\" --- Ds --- displayed text (like .DS) with no keep -.\" .Ds is obsolete. Change to something from this table: -.\" for this use instead -.\" .Ds .ID -.\" .Ds n .LD (where "n" is a number) -.\" (Numbers don't work in these macros, so ".Ds 5" -.\" comes out the same as ".Ds 0".) -.\" -.de Ds -.nf -.\\$1D \\$2 \\$1 -.ft 1 -.ps \\n(PS -.if \\n(VS>=40 .vs \\n(VSu -.if \\n(VS<=39 .vs \\n(VSp -.. -.de D -.ID \\$1 -.. -.de 0D -.LD -.. -.\" backward compatibility for the Xt spec -.de 5D -.LD -.. -.\" -.\" --- De --- obsolete: use .DE instead -.\" -.de De -.DE -.. -.\" -.\" --- FD --- -.\" -.de FD -.LP -.KS -.TA .5i 3i -.ta .5i 3i -.nf -.. -.\" -.\" --- FN --- -.\" -.de FN -.fi -.KE -.LP -.. -.\" -.\" --- IN --- send an index entry to the stderr -.\" -.de IN -.tm \\n%:\\$1:\\$2:\\$3 -.. -.\" -.\" --- C{ --- -.\" -.de C{ -.KS -.nf -.D -.\" -.\" choose appropriate monospace font -.\" the imagen conditional, 480, -.\" may be changed to L if LB is too -.\" heavy for your eyes... -.\" -.ie "\\*(.T"480" .ft L -.el .ie "\\*(.T"300" .ft L -.el .ie "\\*(.T"202" .ft PO -.el .ie "\\*(.T"aps" .ft CW -.el .ft R -.ps \\n(PS -.ie \\n(VS>40 .vs \\n(VSu -.el .vs \\n(VSp -.. -.\" -.\" --- C} --- -.\" -.de C} -.DE -.R -.. -.\" -.\" --- Pn --- like PN, but use $2; $1 and $3 abut -.\" -.de Pn -.IN \\$2 -.ie t \\$1\fB\^\\$2\^\fR\\$3 -.el \\$1\fI\^\\$2\^\fP\\$3 -.. -.\" -.\" --- PN --- put $1 in boldface and add index entry; $2 abuts -.\" -.de PN -.IN \\$1 -.ie t \fB\^\\$1\^\fR\\$2 -.el \fI\^\\$1\^\fP\\$2 -.. -.\" -.\" --- hI --- add index entry for $1 as header file -.\" -.de hI -.IN <\\$1> -.IN Files <\\$1> -.IN Headers <\\$1> -.. -.\" -.\" --- hN --- put $1 in boldface as header and add index entry; $2 abuts -.\" -.de hN -.hI \\$1 -.ie t <\fB\\$1\fR>\\$2 -.el <\fI\\$1\fP>\\$2 -.. -.\" -.\" --- NT --- -.\" -.de NT -.br -.ne 7 -.ds NO Note -.if \\n(.$ .ds NO \\$1 -.ie n .sp -.el .sp 10p -.ce -\\*(NO -.ie n .sp -.el .sp 5p -.if '\\$1'C' .ce 99 -.if '\\$2'C' .ce 99 -.\" .QS/.QE macros don't exist in older versions of -ms -.ie \\n(GS .QS -.el \{\ -. in +5n -. ll -5n -.\} -.R -.. -.\" -.\" --- NE --- Note End (doug kraft 3/85) -.\" -.de NE -.ce 0 -.ie \\n(GS .QE -.el \{\ -. in -5n -. ll +5n -.\} -.ie n .sp -.el .sp 10p -.. -.\" -.\" --- nH --- numbered header (like NH) but with automatic TOC entry -.\" usage: .nH level "section title, preferable in quotes" -.\" -.de nH -.NH \\$1 -\\$2 -.XS -\\*(SN \\$2 -.XE -.. -.\" -.\" --- sM --- put start-marker in margin -.\" -.de sM -.KS -.sp 1 -\\h'-0.5i'\\L'-1v'\\v'1p'\\l'1v'\\v'1v-1p' -.sp -1 -.. -.\" -.\" --- eM --- put end-marker in margin -.\" -.de eM -.sp -1 -\\h'-0.5i'\\L'-1v'\\v'1v+1p'\\l'1v'\\v'-1p' -.sp 1 -.KE -.. -.\" -.\" --- YZ --- finish up; $1 is the starting page number of the TOC -.\" -.de YZ -. \" Force there to be an even number of pages, so the table of -. \" contents doesn't end up on the back of the last page in -. \" the case of duplex printing. -.if o .bp -. \" Emit a .pn directive with one plus the last page number. - \" This will be the number of the first page of the index. -.nr YZ \\n%+1 -.tm .pn \\n(YZ -. \" Issue the table of contents, setting roman numerals, -. \" and redefining the footer to use them. -.bp \\$1 -.af PN i -.EF ''\\\\\\\\n(PN'' -.OF ''\\\\\\\\n(PN'' -. \" Why all the backslashes? This string is evaluated -. \" three times: 1) during the definition of this macro, -. \" 2) when the .EF and .OF macros are expanded, and 3) -. \" when the bottom-of-page trap is invoked. Thus, -. \" eight backslashes are reduced to one in the final output. -.PX -.. diff --git a/doc/xsmp.ms b/doc/xsmp.ms deleted file mode 100644 index 7ab2cf6..0000000 --- a/doc/xsmp.ms +++ /dev/null @@ -1,1623 +0,0 @@ -.\" Use tbl, -ms, and macros.t -.\" $Xorg: xsmp.ms,v 1.3 2000/08/17 19:42:19 cpqbld Exp $ -.EH '''' -.OH '''' -.EF '''' -.OF '''' -.ps 10 -.nr PS 10 -\& -.TL -\s+2\fBX Session Management Protocol\fP\s-2 -.sp -X.Org Standard -.sp -X Version 11, Release 7 -.sp -\*(xV -.AU -Mike Wexler -.AI -Kubota Pacific Computer, Inc. -.AB -.LP -This document specifies a protocol that facilitates the management of groups -of client applications by a session manager. The session manager can cause -clients to save their state, to shut down, and to be restarted into a -previously saved state. This protocol is layered on top of the X.Org -ICE protocol. -.AE -.LP -.bp -\& -.sp 8 -.LP -.DS C -X Window System is a trademark of The Open Group. -.sp -Copyright \(co 1992, 1993, 1994, 2002 The Open Group. -.DE -.sp 3 -.LP -Permission is hereby granted, free of charge, to any person obtaining a copy -of this software and associated documentation files (the ``Software''), to deal -in the Software without restriction, including without limitation the rights -to use, copy, modify, merge, publish, distribute, sublicense, and/or sell -copies of the Software, and to permit persons to whom the Software is -furnished to do so, subject to the following conditions: -.LP -The above copyright notice and this permission notice shall be included in -all copies or substantial portions of the Software. -.LP -THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR -IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, -FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE -X CONSORTIUM BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN -AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN -CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. -.af PN i -.EF ''\\\\n(PN'' -.OF ''\\\\n(PN'' -.bp 1 -.af PN 1 -.EH '\fBX Session Management Protocol\fP''\fB\*(xV\fP' -.OH '\fBX Session Management Protocol\fP''\fB\*(xV\fP' -.EF ''\fB\\\\n(PN\fP'' -.OF ''\fB\\\\n(PN\fP'' -.nH 1 "Acknowledgements" -.LP -First I would like to thank the entire ICCCM and Intrinsics working groups for -the comments and suggestions. I would like to make special thanks to the -following people (in alphabetical order), Jordan Brown, Ellis Cohen, Donna -Converse, Vania Joloboff, Stuart Marks, Ralph Mor and Bob Scheifler. -.nH 1 "Definitions and Goals" -.LP -The purpose of the X Session Management Protocol (XSMP) is to provide a -uniform mechanism for users to save and restore their sessions. A -\fIsession\fP is a group of clients, each of which has a particular state. -The session is controlled by a network service called the \fIsession -manager\fP\^. The session manager issues commands to its clients on behalf -of the user. These commands may cause clients to save their state or to -terminate. It is expected that the client will save its state in such a -way that the client can be restarted at a later time and resume its -operation as if it had never been terminated. A client's state might -include information about the file currently being edited, the current -position of the insertion point within the file, or the start of an -uncommitted transaction. -The means by which clients are -restarted is unspecified by this protocol. -.LP -For purposes of this protocol, a \fIclient\fP of the session manager is -defined as a connection to the session manager. A client is typically, -though not necessarily, a process running an application program connected -to an X Window System display. However, a client may be connected to more -than one X display or not be connected to any X displays at all. -.LP -This protocol is layered on top of the X Consortium's ICE protocol and relies on -the ICE protocol to handle connection management and authentication. -.LP -.nH 1 "Overview of the Protocol" -.LP -Clients use XSMP to register themselves with the session manager (SM). When -a client starts up, it should connect to the SM. The client should remain -connected for as long as it runs. A client may resign from the session by -issuing the proper protocol messages before disconnecting. Termination of -the connection without notice will be taken as an indication that the client -died unexpectedly. -.LP -Clients are expected to save their state in such a way as to allow multiple -instantiations of themselves to be managed independently. A unique value -called a \fIclient-ID\fP is provided by the protocol for the purpose of -disambiguating multiple instantiations of clients. Clients may use this ID, -for example, as part of a filename in which to store the state for a -particular instantiation. The client-ID should be saved as part of the -command used to restart this client (the \fIRestartCommand\fP\^) so that the -client will retain the same ID after it is restarted. Certain small pieces -of state might also be stored in the RestartCommand. For example, an X11 client -might place a `\-twoWindow' option in its RestartCommand to indicate that it -should start up in two window mode when it is restarted. -.LP -The client finds the network address of the SM in a system-dependent way. -On POSIX systems an environment variable called SESSION_MANAGER will contain -a list of network IDs. Each id will contain the transport name followed by a -slash and the (transport-specific) -address. A TCP/IP address would look like this: -.ID - \fCtcp/\fP\fIhostname\fP\^\fC:\fP\^\fIportnumber\fP -.DE -where the hostname is a fully qualified domain name. -A Unix Domain address looks like this: -.ID - \fClocal/\fP\fIhostname\fP\^\fC:\fP\^\fIpath\fP -.DE -A DECnet address would look like this: -.ID - \fCdecnet/\fP\fInodename\fP\^\fC::\fP\^\fIobjname\fP -.DE -If multiple network IDs are specified, they should be separated by commas. -.NT Rationale -There was much discussion over whether the XSMP protocol should use X as -the transport protocol or whether it should use its own independent -transport. It was decided that it would use an independent protocol for -several reasons. First, the Session Manager should be able to -manage programs that -do not maintain an X connection. Second, the X protocol is not appropriate to -use as a general-purpose transport protocol. Third, a session might -span multiple displays. -.LP -The protocol is connection based, because there is no other way for the SM -to determine reliably when clients terminate. -.LP -It should be noted that this protocol introduces another single point of -failure into the system. Although it is possible for clients to continue -running after the SM has exited, this will probably not be the case in -normal practice. Normally the program that starts the SM will consider the -session to be terminated when the SM exits (either normally or abnormally). -.LP -To get around this would require some sort of -rendezvous server that would also introduce a single point of failure. In the -absence of a generally available rendezvous server, XSMP is kept simple in -the hopes of making simple reliable SMs. -.NE -.LP -Some clients may wish to manage the programs they start. For example, a -mail program could start a text editor for editing the text of a mail -message. A client that does this is a session manager itself; -it should supply the clients it starts with the appropriate connection -information (i.e., the SESSION_MANAGER environment variable) that specifies -a connection to itself instead of to the top level session manager. -.LP -Each client has associated with it a list of properties. -A property set by one client is not visible to any other client. -These properties are used for the client to inform the SM of the client's -current state. -When a client initially connects to the SM, there are no properties set. -.nH 1 "Data Types" -.LP -XSMP messages contain several types of data. Both the SM and the client -always send messages in their native byte order. Thus, both sides may need -to byte-swap the messages received. The need to do byte-swapping is -determined at run-time by the ICE protocol. -.LP -If an invalid value is specified for a field of any of the enumerated types, a -.PN BadValue -error message must be sent by the receiver of the message to the sender of the -message. -.br -.ne 6 -.TS H -l lw(4.5i). -_ -.sp 6p -.B -Type Name Description -.R -.sp 6p -_ -.sp 6p -.TH -BOOL T{ -.PN False -or -.PN True -T} -INTERACT_STYLE T{ -.PN None , -.PN Errors , -or -.PN Any -T} -DIALOG_TYPE T{ -.PN Error -or -.PN Normal -T} -SAVE_TYPE T{ -.PN Global , -.PN Local , -or -.PN Both -T} -CARD8 a one-byte unsigned integer -CARD16 a two-byte unsigned integer -CARD32 a four-byte unsigned integer -ARRAY8 a sequence of CARD8s -LISTofARRAY8 a sequence of ARRAY8s -PROPERTY a property name (an ARRAY8), a type name, and a value of that type -LISTofPROPERTY T{ -a counted collection of \%PROPERTYs. -T} -.sp 6p -_ -.TE -.nH 1 "Protocol Setup and Message Format" -.LP -To start the XSMP protocol, the client sends the server an ICE -.PN ProtocolSetup -message. -All XSMP messages are in the standard ICE message format. The message's major -opcode is assigned to XSMP by ICE at run-time. The different parties -(client and SM) may be assigned different major opcodes for XSMP. Once -assigned, all XSMP messages issued by this party will use the same major -opcode. The message's minor opcode specifies which protocol message this -message contains. -.nH 1 "Client Identification String" -.LP -A client ID is a string of XPCS characters encoded in ISO Latin 1 (ISO -8859-1). No null characters are allowed in this string. The client ID -string is used in the -.PN Register\%Client -and -.PN Register\%ClientReply -messages. -.LP -Client IDs consist of the pieces described below. The ID is -formed by concatenating the pieces in sequence, without -separator characters. All pieces are padded on the left -with '0' characters -so as to fill the specified length. -Decimal numbers are -encoded using the characters `0' through `9', and -hexadecimal numbers using the characters `0' through `9' -and `A' through `F'. -.IP \(bu 4 -Version. This is currently the character `1'. -.IP \(bu 4 -Address type and address. The address type will be one of -.DS -.ta 0.5i -`1' a 4-byte IPv4 address encoded as 8 hexadecimal digits -`2' a 6-byte DECNET address encoded as 12 hexadecimal digits -`6' a 16-byte IPv6 address encoded as 32 hexadecimal digits -.DE -.IP -The address is the one of the network addresses of the machine where the -session manager (not the client) is running. For example, the IP address -198.112.45.11 would be encoded as the string \*QC6702D0B\*U. -.IP \(bu 4 -Time stamp. A 13-digit decimal number specifying the number of -milliseconds since 00:00:00 UTC, January 1, 1970. -.IP \(bu 4 -Process-ID type and process-ID. The process-ID type will be one of -.DS -.ta 0.5i -`1' a POSIX process-ID encoded as a 10-digit decimal number. -.DE -.IP -The process-ID is the process-ID of the session manager, not of a client. -.IP \(bu 4 -Sequence number. This is a four-digit decimal number. It is incremented -every time the session manager creates an ID. After reaching \*Q9999\*U it -wraps to \*Q0000\*U. -.NT "Rationale" -Once a client ID has been assigned to the client, the client keeps -this ID indefinitely. If the client is terminated and restarted, it -will be reassigned the same ID. It is desirable to be able to pass -client IDs around from machine to machine, from user to user, and -from session manager to session manager, while retaining the -identity of the client. This, combined with the indefinite -persistence of client IDs, means that client IDs need to be globally -unique. The construction specified above will ensure that any -client ID created by any user, session manager, and machine will be -different from any other. -.NE -.nH 1 "Protocol" -.LP -The protocol consists of a sequence of messages as described below. Each -message type is specified by an ICE minor opcode. A given message type is -sent either from a client to the session manager or from the session manager -to a client; the appropriate direction is listed with each message's -description. For each message type, the set of -valid responses and possible error -messages are listed. The ICE severity is given in parentheses following -each error class. -.LP -.sM -.PN RegisterClient -[Client \(-> SM] -.RS -.LP -\fIprevious-ID\fP\^: ARRAY8 -.LP -Valid Responses: -.PN RegisterClientReply -.LP -Possible Errors: -.PN BadValue -.Pn ( CanContinue ) -.RE -.eM -.LP -The client must send this message to the SM to register the client's existence. -If a client is being restarted from a previous -session, the previous-ID field must contain the client ID from the -previous session. -For new clients, previous-ID should be of zero length. -.LP -If previous-ID is not valid, the SM will send a -.PN BadValue -error message to the client. -At this point the SM reverts to the register state and waits for another -.PN RegisterClient . -The client should then send a -.PN RegisterClient -with a null previous-ID field. -.LP -.sM -.PN RegisterClientReply -[Client \(<- SM] -.RS -.LP -\fIclient-ID\fP\^: ARRAY8 -.RE -.eM -.LP -The client-ID specifies a unique identification for this client. -If the client had specified an ID in the previous-ID field of the -.PN RegisterClient -message, client-ID will be identical to the previously specified ID. If -previous-ID was null, client-ID will be a unique ID freshly generated by the -SM. The client-ID format is specified in section 6. -.LP -If the client didn't supply a previous-ID field to the -.PN Register\%Client -message, the SM must send a -.PN SaveYourself -message with type = Local, shutdown = False, interact-style = None, -and fast = False immediately after the -.PN RegisterClientReply . -The client should respond to this like any other -.PN Save\%Yourself -message. -.LP -.sM -.PN SaveYourself -[Client \(<- SM] -.RS -.LP -\fItype\fP\^: SAVE_TYPE -.br -\fIshutdown\fP\^: BOOL -.br -\fIinteract-style\fP\^: INTERACT_STYLE -.br -\fIfast\fP\^: BOOL -.LP -Valid Responses: -.PN SetProperties , -.PN DeleteProperties , -.PN GetProperties , -.PN SaveYourselfDone , -.PN SaveYourselfPhase2Request , -.PN InteractRequest -.RE -.eM -.LP -The SM sends this message to a client to ask it to save -its state. The client writes a state file, if necessary, -and, if necessary, uses -.PN SetProperties -to inform the SM of -how to restart it and how to discard the saved state. During -this process it can, if allowed by interact-style, request -permission to interact with the user by sending an -.PN InteractRequest -message. -After the state has been saved, or -if it cannot be successfully saved, and the properties -are appropriately set, the client sends a -.PN SaveYourselfDone -message. -If the client wants to save additional information after all the -other clients have finished changing their own state, the client -should send -.PN SaveYourselfPhase2Request -instead of -.PN SaveYourselfDone . -The client must then -freeze interaction with the user and wait until it -receives a -.PN SaveComplete , -.PN Die , -or a -.PN ShutdownCancelled -message. -.LP -If interact-style is -.PN None , -the client must not interact with the -user while saving state. If the interact-style is -.PN Errors , -the client -may interact with the user only if an error condition arises. If -interact-style is -.PN Any , -then the client may interact with the user for -any purpose. -This is done by sending an -.PN Interact\%Request -message. The SM will send an -.PN Interact -message to -each client that sent an -.PN Interact\%Request . -The client must postpone all -interaction until it gets the -.PN Interact -message. When the client is done -interacting it should send the SM an -.PN Interact\%Done -message. The -.PN Interact\%Request -message can be sent any time after a -.PN Save\%Yourself -and before a -.PN Save\%Yourself\%Done . -.LP -Unusual circumstances may dictate multiple interactions. -The client may initiate as many -.PN Interact\%Request -\- -.PN Interact -\- -.PN InteractDone -sequences as it needs before it sends -.PN SaveYourselfDone . -.LP -When a client receives -.PN Save\%Yourself -and has not yet responded -.PN Save\%Yourself\%Done -to a previous -.PN Save\%Yourself , -it must send a -.PN Save\%Yourself\%Done -and may then begin responding as appropriate -to the newly received -.PN Save\%Yourself . -.LP -The type field specifies the type of information that should be saved: -.PN Global , -.PN Local , -or -.PN Both . -The -.PN Local -type indicates that the application must update the -properties to reflect its current state, send a -.PN Save\%Yourself\%Done -and continue. Specifically it should save enough information to restore -the state as seen by the user of this client. It should not affect the -state as seen by other users. -The -.PN Global -type indicates that the user wants the client to -commit all of its data to permanent, globally-accessible -storage. -.PN Both -indicates that the client should do both of these. If -.PN Both -is specified, the client should first commit the data to permanent storage -before updating its SM properties. -.NT Examples -If a word processor was sent a -.PN SaveYourself -with a type of -.PN Local , -it could create a temporary file that included the -current contents of the file, the location of the cursor, and -other aspects of the current editing session. -It would then update its -.PN Restart\%Command -property with enough information to find the temporary file, -and its -.PN Discard\%Command -with enough information to remove it. -.LP -If a word processor was sent a -.PN SaveYourself -with a type of -.PN Global , -it would simply save the currently edited file. -.LP -If a word processor was sent a -.PN SaveYourself -with a type of -.PN Both , -it would first save the currently edited file. It would then create a -temporary file with information such as the current position of the cursor -and what file is being edited. -It would then update its -.PN Restart\%Command -property with enough information to find the temporary file, -and its -.PN Discard\%Command -with enough information to remove it. -.LP -Once the SM has send -.PN SaveYourself -to a client, it can't send another -.PN SaveYourself -to that client until the client either -responds with a -.PN SaveYourselfDone -or the SM sends a -.PN ShutdownCancelled . -.NE -.NT "Advice to Implementors" -If the client stores local any state in a file or similar -\*Qexternal\*U storage, it must create a distinct -copy in response to each -.PN SaveYourself -message. -It \fImust not\fP simply refer to a previous copy, because -the SM may discard that previous saved state using a -.PN DiscardCommand -without knowing that it is needed for the new checkpoint. -.NE -.LP -The shutdown field specifies whether the system is being shut down. -.NT Rationale -The interaction -may be different depending on whether or not shutdown is set. -.NE -The client must save and then must prevent interaction -until it receives a -.PN SaveComplete , -.PN Die , -or a -.PN Shutdown\%Cancelled , -because anything the user does after the save will be lost. -.LP -The fast field specifies whether or not the client should save its state as quickly as -possible. For example, if the SM knows that power is about to fail, it -should set the fast field to -.PN True . -.LP -.sM -.PN SaveYourselfPhase2 -[Client \(<- SM] -.RS -.LP -.LP -Valid Responses: -.PN SetProperties , -.PN DeleteProperties , -.PN GetProperties , -.PN SaveYourselfDone , -.PN InteractRequest -.RE -.eM -.LP -The SM sends this message to a client that has previously sent a -.PN SaveYourselfPhase2Request -message. -This message informs the client that all other clients are in a fixed -state and this client can save state that is associated with other clients. -.NT "Rationale" -Clients that manager other clients (window managers, workspace managers, etc) -need to know when all clients they are managing are idle, so that the manager -can save state related to each of the clients without being concerned with -that state changing. -.NE -The client writes a state file, if necessary, and, if necessary, uses -.PN SetProperties -to inform the SM of -how to restart it and how to discard the saved state. During -this process it can request -permission to interact with the user by sending an -.PN InteractRequest -message. -This should only be done if an error occurs that requires user interaction -to resolve. -After the state has been saved, or -if it cannot be successfully saved, and the properties -are appropriately set, the client sends a -.PN SaveYourselfDone -message. -.LP -.LP -.sM -.PN SaveYourselfRequest -[Client \(-> SM] -.RS -.LP -\fItype\fP\^: SAVE_TYPE -.br -\fIshutdown\fP\^: BOOL -.br -\fIinteract-style\fP\^: INTERACT_STYLE -.br -\fIfast\fP\^: BOOL -.br -\fIglobal\fP\^: BOOL -.LP -Valid Responses: -.PN SaveYourself -.RE -.eM -.LP -An application sends this to the SM to request a checkpoint. -When the SM receives this request it may generate a -.PN SaveYourself -message in response and it may leave the fields intact. -.NT Example -A vendor of a UPS (Uninterruptible Power Supply) might include an -SM client that would monitor the status of the UPS and generate -a fast shutdown if the power is about to be lost. -.NE -.LP -If global is set to -.PN True , -then the resulting -.PN SaveYourself -should be -sent to all applications. If global is set to -.PN False , -then the resulting -.PN SaveYourself -should be sent to the application that sent the -.PN Save\%Yourself\%Request . -.LP -.sM -.PN InteractRequest -[Client \(-> SM] -.RS -.LP -\fIdialog-type\fP\^: DIALOG_TYPE -.LP -Valid Responses: -.PN Interact , -.PN ShutdownCancelled -.LP -Possible Errors: -.PN BadState -.Pn ( CanContinue ) -.RE -.eM -.LP -During a checkpoint or session-save operation, -only one client at a time might be granted the privilege of interacting with -the user. The -.PN InteractRequest -message causes the SM to emit an -.PN Interact -message at some later time if the shutdown is not cancelled -by another client first. -.LP -The dialog-type field specifies either -.PN Errors , -indicating that the -client wants to start an error dialog or -.PN Normal , -meaning the client -wishes to start a non-error dialog. -.LP -.sM -.PN Interact -[Client \(<- SM] -.RS -.LP -Valid Responses: -.PN InteractDone -.LP -.RE -.eM -.LP -This message grants the client the privilege of interacting with the -user. When the client is done interacting with the user it must -send an -.PN InteractDone -message to the SM unless a shutdown cancel is received. -.NT "Advice to Implementors" -If a client receives a ShutdownCancelled after receiving an -.PN Interact -message, but before sending a -.PN InteractDone , -the client should abort the interaction and send a -.PN SaveYourselfDone . -.NE -.LP -.sM -.PN InteractDone -[Client \(-> SM] -.RS -.LP -\fIcancel-shutdown\fP\^: BOOL -.br -.LP -Valid Responses: -.PN ShutdownCancelled -.LP -.RE -.eM -.LP -This message is used by a client to notify the SM that it is done interacting. -.LP -Setting the cancel-shutdown field to -.PN True -indicates that -the user has requested that the entire shutdown be cancelled. -Cancel-shutdown may only be -.PN True -if the corresponding -.PN SaveYourself -message specified -.PN True -for the shutdown field and -.PN Any -or -.PN Errors -for the interact-style field. Otherwise, cancel-shutdown must be -.PN False . -.LP -.sM -.PN SaveYourselfDone -[Client \(-> SM] -.RS -.LP -\fIsuccess\fP\^: BOOL -.LP -Valid Responses: -.PN SaveComplete , -.PN Die , -.PN ShutdownCancelled -.LP -.RE -.eM -.LP -This message is sent by a client to indicate that all of the properties -representing its state have been updated. -After sending -.PN SaveYourselfDone -the client must -wait for a -.PN SaveComplete , -.PN ShutdownCancelled , -or -.PN Die -message before changing its state. -If the -.PN SaveYourself -operation was successful, then the client -should set the success field to -.PN True ; -otherwise the client should set -it to -.PN False . -.NT Example -If a client tries to save its state and runs out of disk space, -it should return -.PN False -in the success -field of the -.PN SaveYourselfDone -message. -.NE -.LP -.sM -.PN SaveYourselfPhase2Request -[Client \(-> SM] -.RS -.LP -Valid Responses: -.PN ShutdownCancelled , -.PN SaveYourselfPhase2 -.LP -.RE -.eM -.LP -This message is sent by a client to indicate that it needs to be informed -when all the other clients are quiescent, so it can continue its state. -.LP -.sM -.PN Die -[Client \(<- SM] -.RS -.LP -Valid Responses: -.PN ConnectionClosed -.RE -.eM -.LP -When the SM wants a client to die it sends a -.PN Die -message. Before the client dies it responds -by sending a -.PN ConnectionClosed -message and may then close -its connection to the SM at any time. -.LP -.sM -.PN SaveComplete -[Client \(<- SM] -.RS -.LP -Valid Responses: -.RE -.eM -.LP -When the SM is done with a checkpoint, it will send each of the clients a -.PN SaveComplete -message. -The client is then free to change its state. -.LP -.sM -.PN ShutdownCancelled -[Client \(<- SM] -.RS -.RE -.eM -.LP -The shutdown currently in process has been aborted. The client can now -continue as if the shutdown had never happened. -If the client has not sent -.PN SaveYourselfDone -yet, the client can either -abort the save and send -.PN SaveYourselfDone -with the success field -set to -.PN False , -or it can continue with the save and send a -.PN SaveYourselfDone -with the success field set to reflect the outcome -of the save. -.LP -.sM -.PN ConnectionClosed -[Client \(-> SM] -.RS -.LP -\fIreason\fP\^: LISTofARRAY8 -.RE -.eM -.LP -Specifies that the client has decided to terminate. -It should be immediately followed by closing the connection. -.LP -The reason field specifies why the client is resigning from the session. It -is encoded as an array of Compound Text strings. If the resignation is -expected by the user, there will typically be zero ARRAY8s here. But if the -client encountered an unexpected fatal error, the error message (which might -otherwise be printed on stderr on a POSIX system) should be forwarded to the -SM here, one ARRAY8 per line of the message. It is the responsibility of -the SM to display this reason to the user. -.LP -After sending this message, the client must not send any additional XSMP -messages to the SM. -.NT "Advice to Implementors" -If additional messages are received, they should be discarded. -.NE -.NT Rationale -The reason for sending the -.PN ConnectionClosed -message before -actually closing the connections is that some transport protocols will -not provide immediate notification of connection closure. -.NE -.LP -.sM -.PN SetProperties -[Client \(-> SM] -.RS -.LP -\fIproperties\fP: LISTofPROPERTY -.RE -.eM -.LP -Sets the specified properties to the specified values. -Existing properties not specified in the -.PN Set\%Properties -message are unaffected. -Some properties have predefined semantics. -See section 11, \*QPredefined Properties.\*U -.LP -The protocol specification recommends that property names used -for properties not defined by the standard should begin with an underscore. -To prevent conflicts among organizations, -additional prefixes should be chosen -(for example, _KPC_FAST_SAVE_OPTION). -The organizational prefixes should be registered with the X Registry. -The XSMP reserves all property names not beginning with an underscore for -future use. -.LP -.sM -.PN DeleteProperties -[Client \(-> SM] -.RS -.LP -.br -\fIproperty-names\fP: LISTofARRAY8 -.RE -.eM -.LP -Removes the named properties. -.LP -.sM -.PN GetProperties -[Client \(-> SM] -.RS -.LP -Valid Responses: -.PN GetPropertiesReply -.RE -.eM -.LP -Requests that the SM respond with the -values of all the properties for this client. -.LP -.sM -.PN GetPropertiesReply -[Client \(<- SM] -.RS -.LP -\fIvalues\fP\^: LISTofPROPERTY -.RE -.eM -.LP -This message is sent in reply to a -.PN GetProperties -message and includes -the values of all the properties. -.nH 1 "Errors" -.LP -When the receiver of a message detects an error condition, -the receiver sends -an ICE error message to the sender. -There are only two types of errors that are used by the XSMP: -.PN BadValue -and -.PN BadState . -These are both defined in the ICE protocol. -.LP -Any message received out-of-sequence -will generate a -.PN BadState -error message. -.nH 1 "State Diagrams" -.LP -These state diagrams are designed to cover all actions of both -the client and the SM. -.nH 2 "Client State Diagram" -.LP -.nf -.DS L 0 -\fIstart:\fP - ICE protocol setup complete \(-> \fCregister\fP -.DE -.sp -.DS L 0 -\fIregister:\fP - send \fBRegisterClient\fP \(-> \fCcollect-id\fP -.DE -.sp -.DS L 0 -\fIcollect-id:\fP - receive \fBRegisterClientReply\fP \(-> \fCidle\fP -.DE -.sp -.DS L 0 -\fIshutdown-cancelled:\fP - send \fBSaveYourselfDone\fP \(-> \fCidle\fP -.DE -.sp -.DS L 0 -\fIidle:\fP [Undoes any freeze of interaction with user.] - receive \fBDie\fP \(-> \fCdie\fP - receive \fBSaveYourself\fP \(-> \fCfreeze-interaction\fP - send \fBGetProperties\fP \(-> \fCidle\fP - receive \fBGetPropertiesReply\fP \(-> \fCidle\fP - send \fBSetProperties\fP \(-> \fCidle\fP - send \fBDeleteProperties\fP \(-> \fCidle\fP - send \fBConnectionClosed\fP \(-> \fCconnection-closed\fP - send \fBSaveYourselfRequest\fP \(-> \fCidle\fP -.DE -.sp -.DS L 0 -\fIdie:\fP - send \fBConnectionClosed\fP \(-> \fCconnection-closed\fP -.DE -.sp -.DS L 0 -\fIfreeze-interaction:\fP - freeze interaction with user \(-> \fCsave-yourself\fP -.DE -.sp -.DS L 0 -\fIsave-yourself:\fP - receive \fBShutdownCancelled\fP \(-> \fCshutdown-cancelled\fP - send \fBSetProperties\fP \(-> \fCsave-yourself\fP - send \fBDeleteProperties\fP \(-> \fCsave-yourself\fP - send \fBGetProperties\fP \(-> \fCsave-yourself\fP - receive \fBGetPropertiesReply\fP \(-> \fCsave-yourself\fP - send \fBInteractRequest\fP \(-> \fCinteract-request\fP - send \fBSaveYourselfPhase2Request\fP -> waiting-for-phase2 - if shutdown mode: - send \fBSaveYourselfDone\fP \(-> \fCsave-yourself-done\fP - otherwise: - send \fBSaveYourselfDone\fP \(-> \fCidle\fP -.DE -.sp -.DS L 0 -\fIwaiting-for-phase2:\fP - receive \fBShutdownCancelled\fP \(-> \fCshutdown-cancelled\fP - receive \fBSaveYourselfPhase2\fP \(-> \fCphase2\fP -.DE -.sp -.DS L 0 -\fIphase2:\fP - receive \fBShutdownCancelled\fP \(-> \fCshutdown-cancelled\fP - send \fBSetProperties\fP \(-> \fCsave-yourself\fP - send \fBDeleteProperties\fP \(-> \fCsave-yourself\fP - send \fBGetProperties\fP \(-> \fCsave-yourself\fP - receive \fBGetPropertiesReply\fP \(-> \fCsave-yourself\fP - send \fBInteractRequest\fP \(-> \fCinteract-request\fP (errors only) - if shutdown mode: - send \fBSaveYourselfDone\fP \(-> \fCsave-yourself-done\fP - otherwise: - send \fBSaveYourselfDone\fP \(-> \fCidle\fP -.DE -.sp -.DS L 0 -\fIinteract-request:\fP - receive \fBInteract\fP \(-> \fCinteract\fP - receive \fBShutdownCancelled\fP \(-> \fCshutdown-cancelled\fP -.DE -.sp -.DS L 0 -\fIinteract:\fP - send \fBInteractDone\fP \(-> \fCsave-yourself\fP - receive \fBShutdownCancelled\fP \(-> \fCshutdown-cancelled\fP -.DE -.sp -.DS L 0 -\fIsave-yourself-done:\fP (changing state is forbidden) - receive \fBSaveComplete\fP \(-> \fCidle\fP - receive \fBDie\fP \(-> \fCdie\fP - receive \fBShutdownCancelled\fP \(-> \fCidle\fP -.DE -.sp -.DS L 0 -\fIconnection-closed:\fP - client stops participating in session -.DE -.ne 1i -.nH 2 "Session Manager State Diagram" -.LP -.nf -.DS L 0 -\fIstart:\fP - receive \fBProtocolSetup\fP \(-> \fCprotocol-setup\fP -.DE -.sp -.DS L 0 -\fIprotocol-setup:\fP - send \fBProtocolSetupReply\fP \(-> \fCregister\fP -.DE -.sp -.DS L 0 -\fIregister:\fP - receive \fBRegisterClient\fP \(-> \fCacknowledge-register\fP -.DE -.sp -.DS L 0 -\fIacknowledge-register:\fP - send \fBRegisterClientReply\fP \(-> \fCidle\fP -.DE -.sp -.DS L 0 -\fIidle:\fP - receive \fBSetProperties\fP \(-> \fCidle\fP - receive \fBDeleteProperties\fP \(-> \fCidle\fP - receive \fBConnectionClosed\fP \(-> \fCstart\fP - receive \fBGetProperties\fP \(-> \fCget-properties\fP - receive \fBSaveYourselfRequest\fP \(-> \fCsave-yourself\fP - send \fBSaveYourself\fP \(-> \fCsaving-yourself\fP -.DE -.sp -.DS L 0 -\fIsave-yourself:\fP - send \fBSaveYourself\fP \(-> \fCsaving-yourself\fP -.DE -.sp -.DS L 0 -\fIget-properties:\fP - send \fBGetPropertiesReply\fP \(-> \fCidle\fP -.DE -.sp -.DS L 0 -\fIsaving-get-properties:\fP - send \fBGetPropertiesReply\fP \(-> \fCsaving-yourself\fP -.DE -.sp -.DS L 0 -\fIsaving-yourself:\fP - receive \fBInteractRequest\fP \(-> \fCsaving-yourself\fP - send \fBInteract\fP \(-> \fCsaving-yourself\fP - send \fBShutdownCancelled\fP -> \fCidle\fP - receive \fBInteractDone\fP \(-> \fCsaving-yourself\fP - receive \fBSetProperties\fP \(-> \fCsaving-yourself\fP - receive \fBDeleteProperties\fP \(-> \fCsaving-yourself\fP - receive \fBGetProperties\fP \(-> \fCsaving-get-properties\fP - receive \fBSaveYourselfPhase2Request\fP \(-> \fCstart-phase2\fP - receive \fBSaveYourselfDone\fP \(-> \fCsave-yourself-done\fP -.DE -.sp -.DS L 0 -\fIstart-phase2:\fP - If all clients have sent either \fBSaveYourselfPhase2Request\fP or \fBSaveYourselfDone\fP: - send \fBSaveYourselfPhase2\fP \(-> \fCphase2\fP - else - \(-> \fCsaving-yourself\fP -.DE -.sp -.DS L 0 -\fIphase2:\fP - receive \fBInteractRequest\fP \(-> \fCsaving-yourself\fP - send \fBInteract\fP \(-> \fCsaving-yourself\fP - send \fBShutdownCancelled\fP -> \fCidle\fP - receive \fBInteractDone\fP \(-> \fCsaving-yourself\fP - receive \fBSetProperties\fP \(-> \fCsaving-yourself\fP - receive \fBDeleteProperties\fP \(-> \fCsaving-yourself\fP - receive \fBGetProperties\fP \(-> \fCsaving-get-properties\fP - receive \fBSaveYourselfDone\fP \(-> \fCsave-yourself-done\fP -.DE -.sp -.DS L 0 -\fIsave-yourself-done:\fP - If all clients are saved: - If shutting down: - send \fBDie\fP \(-> \fCdie\fP - otherwise - send \fBSaveComplete\fP \(-> \fCidle\fP -.sp - If some clients are not saved: - \(-> \fCsaving-yourself\fP -.DE -.sp -.DS L 0 -\fIdie:\fP - SM stops accepting connections -.DE -.nH 1 "Protocol Encoding" -.nH 2 "Types" -.LP -.nf -.ta .2i .5i 2.0i -BOOL - 0 False - 1 True -.sp -INTERACT_STYLE - 0 None - 1 Errors - 2 Any -.sp -DIALOG_TYPE - 0 Error - 1 Normal -.sp -SAVE_TYPE - 0 Global - 1 Local - 2 Both -.sp -.ne .75i -ARRAY8 - 4 CARD32 length - n LISTofCARD8 the array - p p = pad (4 + n, 8) -.sp -LISTofARRAY8 - 4 CARD32 count - 4 unused - a ARRAY8 first array - b ARRAY8 second array - \&. - \&. - \&. - q ARRAY8 last array -.sp -PROPERTY - a ARRAY8 name - b ARRAY8 type (XPCS encoded in Latin-1, case sensitive) - c LISTofARRAY8 values -.sp -LISTofPROPERTY - 4 CARD32 count - 4 unused - a PROPERTY first property - b PROPERTY second property - \&. - \&. - \&. - q PROPERTY last property -.nH 2 "Messages" -.LP -XSMP is a sub-protocol of ICE. The major opcode is assigned at run-time -by ICE and is represented here by `?'. -.LP -To start the XSMP protocol, the client sends the server an ICE -.PN ProtocolSetup -message. -The protocol-name field should be specified as \*QXSMP\*U, the major -version of the protocol is 1, the minor version is 0. -These values may change if the protocol is revised. The minor version -number will be incremented if the change is compatible, otherwise the major -version number will be incremented. -.LP -In -.PN ProtocolReply -message sent by the session manager, -the XSMP protocol defines the vendor parameter as product identification -of the session manager, and defines the release parameter as -the software release identification of the session manager. -The session manager should supply this information in the -ICE -.PN ProtocolReply -message. -.LP -.nf -.ta .2i .5i 2.0i -.ne 3 -.PN RegisterClient - 1 ? XSMP - 1 1 opcode - 2 unused - 4 a/8 length of remaining data in 8-byte units - a ARRAY8 previous-ID -.ne 6 -.sp -.PN RegisterClientReply - 1 ? XSMP - 1 2 opcode - 2 unused - 4 a/8 length of remaining data in 8-byte units - a ARRAY8 client-ID -.ne 4 -.sp -.PN SaveYourself - 1 ? XSMP - 1 3 opcode - 2 unused - 4 1 length of remaining data in 8-byte units - 1 SAVE_TYPE type - 1 BOOL shutdown - 1 INTERACT_STYLE interact-style - 1 BOOL fast - 4 unused -.ne 4 -.sp -.PN SaveYourselfRequest - 1 ? XSMP - 1 4 opcode - 2 unused - 4 1 length of remaining data in 8-byte units - 1 SAVE_TYPE type - 1 BOOL shutdown - 1 INTERACT_STYLE interact-style - 1 BOOL fast - 1 BOOL global - 3 unused -.ne 4 -.sp -.PN InteractRequest - 1 ? XSMP - 1 5 opcode - 1 DIALOG_TYPE dialog type - 1 unused - 4 0 length of remaining data in 8-byte units -.ne 4 -.sp -.PN Interact - 1 ? XSMP - 1 6 opcode - 2 unused - 4 0 length of remaining data in 8-byte units -.ne 4 -.sp -.PN InteractDone - 1 ? XSMP - 1 7 opcode - 1 BOOL cancel-shutdown - 1 unused - 4 0 length of remaining data in 8-byte units -.ne 6 -.sp -.PN SaveYourselfDone - 1 ? XSMP - 1 8 opcode - 1 BOOL success - 1 unused - 4 0 length of remaining data in 8-byte units -.ne 4 -.sp -.PN Die - 1 ? XSMP - 1 9 opcode - 2 unused - 4 0 length of remaining data in 8-byte units -.ne 4 -.sp -.PN ShutdownCancelled - 1 ? XSMP - 1 10 opcode - 2 unused - 4 0 length of remaining data in 8-byte units -.ne 4 -.sp -.PN ConnectionClosed - 1 ? XSMP - 1 11 opcode - 2 unused - 4 a/8 length of remaining data in 8-byte units - a LISTofARRAY8 reason -.ne 4 -.sp -.PN SetProperties - 1 ? XSMP - 1 12 opcode - 2 unused - 4 a/8 length of remaining data in 8-byte units - a LISTofPROPERTY properties -.ne 4 -.sp -.PN DeleteProperties - 1 ? XSMP - 1 13 opcode - 2 unused - 4 a/8 length of remaining data in 8-byte units - a LISTofARRAY8 properties -.ne 4 -.sp -.PN GetProperties - 1 ? XSMP - 1 14 opcode - 2 unused - 4 0 length of remaining data in 8-byte units -.ne 4 -.sp -.PN GetPropertiesReply - 1 ? XSMP - 1 15 opcode - 2 unused - 4 a/8 length of remaining data in 8-byte units - a LISTofPROPERTY properties -.ne 4 -.sp -.PN SaveYourselfPhase2Request - 1 ? XSMP - 1 16 opcode - 2 unused - 4 0 length of remaining data in 8-byte units -.ne 4 -.sp -.PN SaveYourselfPhase2 - 1 ? XSMP - 1 17 opcode - 2 unused - 4 0 length of remaining data in 8-byte units - -.sp -.PN SaveComplete - 1 ? XSMP - 1 18 opcode - 2 unused - 4 0 length of remaining data in 8-byte units - -.nH 1 "Predefined Properties" -.LP -All property values are stored in a LISTofARRAY8. If the type of the -property is CARD8, the value is stored as a LISTofARRAY8 with one ARRAY8 -that is one byte long. That single byte contains the CARD8. If the type of -the property is ARRAY8, the value is stored in the first element of a single -element LISTofARRAY8. -.LP -The required properties must be set each time a client -connects with the SM. The properties must be set after -the client sends -.PN RegisterClient -and before the client sends -.PN SaveYourselfDone . -Otherwise, the behavior of -the session manager is not defined. -.LP -Clients may set, get, and delete nonstandard properties. -The lifetime of stored properties does not extend into -subsequent sessions. -.br -.ne 6 -.TS H -l l l c . -_ -.sp 6p -.B -Name Type Posix Type Required? -.R -.sp 6p -_ -.sp 6p -.TH -CloneCommand OS-specific LISTofARRAY8 Yes -CurrentDirectory OS-specific ARRAY8 No -DiscardCommand OS-specific LISTofARRAY8 No* -Environment OS-specific LISTofARRAY8 No -ProcessID OS-specific ARRAY8 No -Program OS-specific ARRAY8 Yes -RestartCommand OS-specific LISTofARRAY8 Yes -ResignCommand OS-specific LISTofARRAY8 No -RestartStyleHint CARD8 CARD8 No -ShutdownCommand OS-specific LISTofARRAY8 No -UserID ARRAY8 ARRAY8 Yes -.sp 6p -_ -.TE -.LP -* Required if any state is stored in an external repository (e.g., state file). -.IP CloneCommand 3 -This is like the -.PN RestartCommand -except it restarts a copy of the -application. The only difference is that the application doesn't -supply its client id at register time. On POSIX systems the type -should be a LISTofARRAY8. -.IP CurrentDirectory 3 -On POSIX-based systems specifies the value of the current directory that -needs to be set up prior to starting the program and should be of type -ARRAY8. -.IP DiscardCommand 3 -The discard command contains a command that when delivered to the host that -the client is running on (determined from the connection), will -cause it to discard any information about the current state. If this command -is not specified, the SM will assume that all of the client's state is encoded -in the -.PN Restart\%Command . -On POSIX systems the type should be LISTofARRAY8. -.IP Environment 3 -On POSIX based systems, this will be of type LISTofARRAY8 where -the ARRAY8s alternate between environment variable name and environment -variable value. -.IP ProcessID 3 -This specifies an OS-specific identifier for the process. On POSIX -systems this should of type ARRAY8 and contain the return value -of getpid() turned into a Latin-1 (decimal) string. -.IP Program 3 -The name of the program that is running. On POSIX systems this -should be the -first parameter passed to execve and should be of type ARRAY8. -.IP RestartCommand 3 -The restart command contains a command that when delivered to the -host that the client is running on (determined from the connection), -will cause the client to restart in -its current state. On POSIX-based systems this is of type LISTofARRAY8 -and each of the elements in the array represents an element in -the argv array. -This restart command should ensure that the client restarts with the specified -client-ID. -.IP ResignCommand 3 -A client that sets the -.PN RestartStyleHint -to -.PN RestartAnyway -uses this property to specify a command -that undoes the effect of the client and removes -any saved state. -.NT Example -A user runs xmodmap. xmodmap registers with the SM, sets -.PN Restart\%Style\%Hint -to -.PN Restart\%Anyway , -and then terminates. In order to allow the SM (at the -user's request) to undo this, xmodmap would register a -.PN Resign\%Command -that undoes the effects of the xmodmap. -.NE -.IP RestartStyleHint 3 -.RS -.LP -If the RestartStyleHint property is present, it will contain the -style of restarting the client prefers. If this flag isn't specified, -.PN RestartIfRunning -is assumed. -The possible values are as follows: -.br -.ne 6 -.TS H -l n. -_ -.sp 6p -.B -Name Value -.R -.sp 6p -_ -.sp 6p -.TH -RestartIfRunning 0 -RestartAnyway 1 -RestartImmediately 2 -RestartNever 3 -.sp 6p -_ -.TE -.LP -The -.PN RestartIfRunning -style is used in the usual case. The client should -be restarted in the next session if it is connected to the -session manager at the end of the current session. -.LP -The -.PN RestartAnyway -style is used to tell the SM that the application -should be restarted in the next session even if it exits before the -current session is terminated. -It should be noted that this is only a hint and the SM -will follow the policies specified by its users in determining what applications -to restart. -.LP -.NT Rationale -This can be specified by a client which supports (as MS-Windows clients -do) a means for the user to indicate while exiting that -restarting is desired. It can also be used for clients that -spawn other clients and then go away, but which want to be -restarted. -.NE -.LP -A client that uses -.PN RestartAnyway -should also set the -.PN ResignCommand -and -.PN ShutdownCommand -properties to commands that undo the state of the client -after it exits. -.LP -The -.PN RestartImmediately -style is like -.PN RestartAnyway , -but in addition, the -client is meant to run continuously. If the client exits, the -SM should try to restart it in the current session. -.NT "Advice to Implementors" -It would be wise to sanity-check the frequency which which -.PN RestartImmediately -clients are restarted, to avoid a sick -client being restarted continuously. -.NE -The -.PN RestartNever -style specifies that the client -does not wish to be restarted in the next session. -.NT "Advice To Implementors" -This should be used rarely, if at all. It will cause the client -to be silently left out of sessions when they are restarted and -will probably be confusing to users. -.NE -.RE -.IP ShutdownCommand -This command is executed at shutdown time to clean up after a client that -is no longer running but retained its state by setting -.PN RestartStyleHint -to -.PN RestartAnyway . -The command must not remove any saved state as the client is still part of -the session. -.NT Example -A client is run at start up time that turns on a camera. This client then -exits. At session shutdown, the user wants the camera turned off. This client -would set the -.PN Restart\%Style\%Hint -to -.PN Restart\%Anyway -and would register a -.PN Shutdown\%Command -that would turn off the camera. -.NE -.IP UserID 3 -Specifies the user's ID. On POSIX-based systems this -will contain the the user's name (the pw_name field of struct passwd). -.\" Finish up. -.YZ 3 diff --git a/doc/xsmp.xml b/doc/xsmp.xml new file mode 100644 index 0000000..cace7a1 --- /dev/null +++ b/doc/xsmp.xml @@ -0,0 +1,1868 @@ + + + + + + + + + X Session Management Protocol + X Consortium Standard + X Version 11, Release 7 + + + MikeWexler + + + Kubota Pacific Computer, Inc + 1992The Open Group + 1993The Open Group + 1994The Open Group + 2002The Open Group + Version 1.0 + X Consortium + X Version 11, Release 7 + + +Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: + +Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: + +The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE X CONSORTIUM BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + +Except as contained in this notice, the name of the X Consortium shall not be used in advertising or otherwise to promote the sale, use or other dealings in this Software without prior written authorization from the X Consortium. + +X Window System is a trademark of The Open Group. + + + +This document specifies a protocol that facilitates the management of groups of client applications by a session manager. The session manager can cause clients to save their state, to shut down, and to be restarted into a previously saved state. This protocol is layered on top of the X.Org ICE protocol. + + + + + +Acknowledgments + +First I would like to thank the entire ICCCM and Intrinsics working groups for the comments and suggestions. I would like to make special thanks to the following people (in alphabetical order), Jordan Brown, Ellis Cohen, Donna Converse, Vania Joloboff, Stuart Marks, Ralph Mor and Bob Scheifler. + + + +Definitions and Goals + +The purpose of the X Session Management Protocol (XSMP) is to provide a uniform mechanism for users to save and restore their sessions. A session is a group of clients, each of which has a particular state. The session is controlled by a network service called the session manager. The session manager issues commands to its clients on behalf of the user. These commands may cause clients to save their state or to terminate. It is expected that the client will save its state in such a way that the client can be restarted at a later time and resume its operation as if it had never been terminated. A client's state might include information about the file currently being edited, the current position of the insertion point within the file, or the start of an uncommitted transaction. The means by which clients are restarted is unspecified by this protocol. + +For purposes of this protocol, a client of the session manager is defined as a connection to the session manager. A client is typically, though not necessarily, a process running an application program connected to an X Window System display. However, a client may be connected to more than one X display or not be connected to any X displays at all. + +This protocol is layered on top of the X Consortium's ICE protocol and relies on the ICE protocol to handle connection management and authentication. + + + + +Overview of the Protocol + +Clients use XSMP to register themselves with the session manager (SM). When a client starts up, it should connect to the SM. The client should remain connected for as long as it runs. A client may resign from the session by issuing the proper protocol messages before disconnecting. Termination of the connection without notice will be taken as an indication that the client died unexpectedly. + +Clients are expected to save their state in such a way as to allow multiple instantiations of themselves to be managed independently. A unique value called a client-ID is provided by the protocol for the purpose of disambiguating multiple instantiations of clients. Clients may use this ID, for example, as part of a filename in which to store the state for a particular instantiation. The client-ID should be saved as part of the command used to restart this client (the RestartCommand) so that the client will retain the same ID after it is restarted. Certain small pieces of state might also be stored in the RestartCommand. For example, an X11 client might place a '-twoWindow' option in its RestartCommand to indicate that it should start up in two window mode when it is restarted. + +The client finds the network address of the SM in a system-dependent way. On POSIX systems an environment variable called SESSION_MANAGER will contain a list of network IDs. Each id will contain the transport name followed by a slash and the (transport-specific) address. A TCP/IP address would look like this: + +tcp/hostname:portnumber + + +where the hostname is a fully qualified domain name. +A Unix Domain address looks like this: + +local/hostname:path + + +A DECnet address would look like this: + +decnet/nodename::objname + + +If multiple network IDs are specified, they should be separated by commas. + + There was much discussion over whether the XSMP protocol should use X as the transport protocol or whether it should use its own independent transport. It was decided that it would use an independent protocol for several reasons. First, the Session Manager should be able to manage programs that do not maintain an X connection. Second, the X protocol is not appropriate to use as a general-purpose transport protocol. Third, a session might span multiple displays. + +The protocol is connection based, because there is no other way for the SM to determine reliably when clients terminate. + +It should be noted that this protocol introduces another single point of failure into the system. Although it is possible for clients to continue running after the SM has exited, this will probably not be the case in normal practice. Normally the program that starts the SM will consider the session to be terminated when the SM exits (either normally or abnormally). + +To get around this would require some sort of rendezvous server that would also introduce a single point of failure. In the absence of a generally available rendezvous server, XSMP is kept simple in the hopes of making simple reliable SMs. + + +Some clients may wish to manage the programs they start. For example, a mail program could start a text editor for editing the text of a mail message. A client that does this is a session manager itself; it should supply the clients it starts with the appropriate connection information (i.e., the SESSION_MANAGER environment variable) that specifies a connection to itself instead of to the top level session manager. + +Each client has associated with it a list of properties. A property set by one client is not visible to any other client. These properties are used for the client to inform the SM of the client's current state. When a client initially connects to the SM, there are no properties set. + + + +Data Types + +XSMP messages contain several types of data. Both the SM and the client always send messages in their native byte order. Thus, both sides may need to byte-swap the messages received. The need to do byte-swapping is determined at run-time by the ICE protocol. + +If an invalid value is specified for a field of any of the enumerated types, a BadValue error message must be sent by the receiver of the message to the sender of the message. + + + + + + + + Type Name + Description + + + + + BOOL + False or True + + + INTERACT_STYLE + None Errors or Any + + + DIALOG_TYPE + Error or Normal + + + SAVE_TYPE + Global Local or Both + + + CARD8 + a one-byte unsigned integer + + + CARD16 + a two-byte unsigned integer + + + CARD32 + a four-byte unsigned integer + + + ARRAY8 + a sequence of CARD8s + + + LISTofARRAY8 + a sequence of ARRAY8s + + + PROPERTY + a property name (an ARRAY8), a type name, and a value of that type + + + LISTofPROPERTY + a counted collection of ­PROPERTYs. + + + + + + + + +Protocol Setup and Message Format + +To start the XSMP protocol, the client sends the server an ICE ProtocolSetup message. All XSMP messages are in the standard ICE message format. The message's major opcode is assigned to XSMP by ICE at run-time. The different parties (client and SM) may be assigned different major opcodes for XSMP. Once assigned, all XSMP messages issued by this party will use the same major opcode. The message's minor opcode specifies which protocol message this message contains. + + + +Client Identification String +A client ID is a string of XPCS characters encoded in ISO Latin 1 (ISO 8859-1). No null characters are allowed in this string. The client ID string is used in the Register­Client and Register­ClientReply messages. + +Client IDs consist of the pieces described below. The ID is formed by concatenating the pieces in sequence, without separator characters. All pieces are padded on the left with '0' characters so as to fill the specified length. Decimal numbers are encoded using the characters '0' through '9', and hexadecimal numbers using the characters '0' through '9' and 'A' through 'F'. + + + Version. This is currently the character '1'. + Address type and address. The address type will be one of + + '1' a 4-byte IPv4 address encoded as 8 hexadecimal digits + '2' a 6-byte DECNET address encoded as 12 hexadecimal digits + '6' a 16-byte IPv6 address encoded as 32 hexadecimal digits + + + +The address is the one of the network addresses of the machine where the session manager (not the client) is running. For example, the IP address 198.112.45.11 would be encoded as the string "QC6702D0B". + + Time stamp. A 13-digit decimal number specifying the number of milliseconds since 00:00:00 UTC, January 1, 1970. + Process-ID type and process-ID. The process-ID type will be one of + +'1' a POSIX process-ID encoded as a 10-digit decimal number. + +The process-ID is the process-ID of the session manager, not of a client. + Sequence number. This is a four-digit decimal number. It is incremented every time the session manager creates an ID. After reaching "Q9999" it wraps to "Q0000". + +Once a client ID has been assigned to the client, the client keeps this ID indefinitely. If the client is terminated and restarted, it will be reassigned the same ID. It is desirable to be able to pass client IDs around from machine to machine, from user to user, and from session manager to session manager, while retaining the identity of the client. This, combined with the indefinite persistence of client IDs, means that client IDs need to be globally unique. The construction specified above will ensure that any client ID created by any user, session manager, and machine will be different from any other. + + + + + + +Protocol +The protocol consists of a sequence of messages as described below. Each message type is specified by an ICE minor opcode. A given message type is sent either from a client to the session manager or from the session manager to a client; the appropriate direction is listed with each message's description. For each message type, the set of valid responses and possible error messages are listed. The ICE severity is given in parentheses following each error class. + +RegisterClient [Client -> SM] + +previous-ID: ARRAY8 + +Valid Responses: RegisterClientReply + +Possible Errors: BadValue (CanContinue) + +The client must send this message to the SM to register the client's existence. If a client is being restarted from a previous session, the previous-ID field must contain the client ID from the previous session. For new clients, previous-ID should be of zero length. + +If previous-ID is not valid, the SM will send a BadValue error message to the client. At this point the SM reverts to the register state and waits for another RegisterClient The client should then send a RegisterClient with a null previous-ID field. + +RegisterClientReply [Client >- SM] + +client-ID: ARRAY8 + +The client-ID specifies a unique identification for this client. If the client had specified an ID in the previous-ID field of the RegisterClient message, client-ID will be identical to the previously specified ID. If previous-ID was null, client-ID will be a unique ID freshly generated by the SM. The client-ID format is specified in section 6. + +If the client didn't supply a previous-ID field to the Register­Client message, the SM must send a SaveYourself message with type = Local, shutdown = False, interact-style = None, and fast = False immediately after the RegisterClientReply The client should respond to this like any other Save­Yourself message. + +SaveYourself [Client >- SM] + +type: SAVE_TYPE +shutdown: BOOL +interact-style: INTERACT_STYLE +fast: BOOL + +Valid Responses: +SetProperties +DeleteProperties +GetProperties +SaveYourselfDone +SaveYourselfPhase2Request +InteractRequest + +The SM sends this message to a client to ask it to save its state. The client writes a state file, if necessary, and, if necessary, uses SetProperties to inform the SM of how to restart it and how to discard the saved state. During this process it can, if allowed by interact-style, request permission to interact with the user by sending an InteractRequest message. After the state has been saved, or if it cannot be successfully saved, and the properties are appropriately set, the client sends a SaveYourselfDone message. If the client wants to save additional information after all the other clients have finished changing their own state, the client should send SaveYourselfPhase2Request instead of SaveYourselfDone The client must then freeze interaction with the user and wait until it receives a SaveComplete Die or a ShutdownCancelled message. + +If interact-style is None the client must not interact with the user while saving state. If the interact-style is Errors the client may interact with the user only if an error condition arises. If interact-style is Any then the client may interact with the user for any purpose. This is done by sending an Interact­Request message. The SM will send an Interact message to each client that sent an Interact­Request The client must postpone all interaction until it gets the Interact message. When the client is done interacting it should send the SM an Interact­Done message. The Interact­Request message can be sent any time after a Save­Yourself and before a Save­Yourself­Done + +Unusual circumstances may dictate multiple interactions. The client may initiate as many Interact­Request - Interact - InteractDone sequences as it needs before it sends SaveYourselfDone + +When a client receives Save­Yourself and has not yet responded Save­Yourself­Done to a previous Save­Yourself it must send a Save­Yourself­Done and may then begin responding as appropriate to the newly received Save­Yourself + +The type field specifies the type of information that should be saved: Global Local or Both The Local type indicates that the application must update the properties to reflect its current state, send a Save­Yourself­Done and continue. Specifically it should save enough information to restore the state as seen by the user of this client. It should not affect the state as seen by other users. The Global type indicates that the user wants the client to commit all of its data to permanent, globally-accessible storage. Both indicates that the client should do both of these. If Both is specified, the client should first commit the data to permanent storage before updating its SM properties. + + +If a word processor was sent a SaveYourself with a type of Local it could create a temporary file that included the current contents of the file, the location of the cursor, and other aspects of the current editing session. It would then update its Restart­Command property with enough information to find the temporary file, and its Discard­Command with enough information to remove it. + +If a word processor was sent a SaveYourself with a type of Global it would simply save the currently edited file. + +If a word processor was sent a SaveYourself with a type of Both it would first save the currently edited file. It would then create a temporary file with information such as the current position of the cursor and what file is being edited. It would then update its Restart­Command property with enough information to find the temporary file, and its Discard­Command with enough information to remove it. + +Once the SM has send SaveYourself to a client, it can't send another SaveYourself to that client until the client either responds with a SaveYourselfDone or the SM sends a ShutdownCancelled + + + +If the client stores local any state in a file or similar "Qexternal" storage, it must create a distinct copy in response to each SaveYourself message. It must not simply refer to a previous copy, because the SM may discard that previous saved state using a DiscardCommand without knowing that it is needed for the new checkpoint. + + +The shutdown field specifies whether the system is being shut down. + +The interaction may be different depending on whether or not shutdown is set. + +The client must save and then must prevent interaction until it receives a SaveComplete Die or a Shutdown­Cancelled because anything the user does after the save will be lost. + +The fast field specifies whether or not the client should save its state as quickly as possible. For example, if the SM knows that power is about to fail, it should set the fast field to True + +SaveYourselfPhase2 [Client -> SM] + +Valid Responses: +SetProperties +DeleteProperties +GetProperties +SaveYourselfDone +InteractRequest + +The SM sends this message to a client that has previously sent a SaveYourselfPhase2Request message. This message informs the client that all other clients are in a fixed state and this client can save state that is associated with other clients. + + +Clients that manager other clients (window managers, workspace managers, etc) need to know when all clients they are managing are idle, so that the manager can save state related to each of the clients without being concerned with that state changing. + +The client writes a state file, if necessary, and, if necessary, uses SetProperties to inform the SM of how to restart it and how to discard the saved state. During this process it can request permission to interact with the user by sending an InteractRequest message. This should only be done if an error occurs that requires user interaction to resolve. After the state has been saved, or if it cannot be successfully saved, and the properties are appropriately set, the client sends a SaveYourselfDone message. + +SaveYourselfRequest [Client -> SM] + +type: SAVE_TYPE +shutdown: BOOL +interact-style: INTERACT_STYLE +fast: BOOL +global: BOOL + +Valid Responses: SaveYourself + +An application sends this to the SM to request a checkpoint. When the SM receives this request it may generate a SaveYourself message in response and it may leave the fields intact. + + A vendor of a UPS (Uninterruptible Power Supply) might include an SM client that would monitor the status of the UPS and generate a fast shutdown if the power is about to be lost. + +If global is set to True then the resulting SaveYourself should be sent to all applications. If global is set to False then the resulting SaveYourself should be sent to the application that sent the Save­Yourself­Request + +InteractRequest [Client -> SM] + +dialog-type: DIALOG_TYPE + +Valid Responses: Interact ShutdownCancelled + +Possible Errors: BadState (CanContinue) + +During a checkpoint or session-save operation, only one client at a time might be granted the privilege of interacting with the user. The InteractRequest message causes the SM to emit an Interact message at some later time if the shutdown is not cancelled by another client first. + +The dialog-type field specifies either Errors indicating that the client wants to start an error dialog or Normal meaning the client wishes to start a non-error dialog. + +Interact [Client >- SM] + +Valid Responses: InteractDone + +This message grants the client the privilege of interacting with the user. When the client is done interacting with the user it must send an InteractDone message to the SM unless a shutdown cancel is received. + If a client receives a ShutdownCancelled after receiving an Interact message, but before sending a InteractDone the client should abort the interaction and send a SaveYourselfDone + +InteractDone [Client -> SM] + +cancel-shutdown: BOOL + +Valid Responses: ShutdownCancelled + +This message is used by a client to notify the SM that it is done interacting. + +Setting the cancel-shutdown field to True indicates that the user has requested that the entire shutdown be cancelled. Cancel-shutdown may only be True if the corresponding SaveYourself message specified True for the shutdown field and Any or Errors for the interact-style field. Otherwise, cancel-shutdown must be False + +SaveYourselfDone [Client -> SM] + +success: BOOL + +Valid Responses: +SaveComplete +Die +ShutdownCancelled + +This message is sent by a client to indicate that all of the properties representing its state have been updated. After sending SaveYourselfDone the client must wait for a SaveComplete ShutdownCancelled or Die message before changing its state. If the SaveYourself operation was successful, then the client should set the success field to True otherwise the client should set it to False + + +If a client tries to save its state and runs out of disk space, it should return False in the success field of the SaveYourselfDone message. + + +SaveYourselfPhase2Request [Client -> SM] + +Valid Responses: +ShutdownCancelled +SaveYourselfPhase2 + +This message is sent by a client to indicate that it needs to be informed when all the other clients are quiescent, so it can continue its state. + +Die [Client >- SM] + +Valid Responses: ConnectionClosed + +When the SM wants a client to die it sends a Die message. Before the client dies it responds by sending a ConnectionClosed message and may then close its connection to the SM at any time. + +SaveComplete [Client -> SM] + +Valid Responses: + +When the SM is done with a checkpoint, it will send each of the clients a SaveComplete message. The client is then free to change its state. + +ShutdownCancelled [Client >- SM] + +The shutdown currently in process has been aborted. The client can now continue as if the shutdown had never happened. If the client has not sent SaveYourselfDone yet, the client can either abort the save and send SaveYourselfDone with the success field set to False or it can continue with the save and send a SaveYourselfDone with the success field set to reflect the outcome of the save. + +ConnectionClosed [Client -> SM] + +reason: LISTofARRAY8 + +Specifies that the client has decided to terminate. It should be immediately followed by closing the connection. + +The reason field specifies why the client is resigning from the session. It is encoded as an array of Compound Text strings. If the resignation is expected by the user, there will typically be zero ARRAY8s here. But if the client encountered an unexpected fatal error, the error message (which might otherwise be printed on stderr on a POSIX system) should be forwarded to the SM here, one ARRAY8 per line of the message. It is the responsibility of the SM to display this reason to the user. + +After sending this message, the client must not send any additional XSMP messages to the SM. + If additional messages are received, they should be discarded. + +The reason for sending the ConnectionClosed message before actually closing the connections is that some transport protocols will not provide immediate notification of connection closure. + +SetProperties [Client -> SM] + +properties: LISTofPROPERTY + +Sets the specified properties to the specified values. Existing properties not specified in the Set­Properties message are unaffected. Some properties have predefined semantics. See section 11, "Predefined Properties." + +The protocol specification recommends that property names used for properties not defined by the standard should begin with an underscore. To prevent conflicts among organizations, additional prefixes should be chosen (for example, _KPC_FAST_SAVE_OPTION). The organizational prefixes should be registered with the X Registry. The XSMP reserves all property names not beginning with an underscore for future use. + +DeleteProperties [Client -> SM] + +property-names: LISTofARRAY8 + +Removes the named properties. + +GetProperties [Client -> SM] + +Valid Responses: GetPropertiesReply + +Requests that the SM respond with the values of all the properties for this client. + +GetPropertiesReply [Client <- SM] + +values: LISTofPROPERTY + +This message is sent in reply to a GetProperties message and includes the values of all the properties. + + + +Errors + +When the receiver of a message detects an error condition, the receiver sends an ICE error message to the sender. There are only two types of errors that are used by the XSMP: BadValue and BadState +These are both defined in the ICE protocol. + +Any message received out-of-sequence will generate a BadState +error message. + + + +State Diagrams +These state diagrams are designed to cover all actions of both the client and the SM. + + +Client State Diagram + + + +start: + ICE protocol setup complete -> register + + +register: + send RegisterClient -> collect-id + + +collect-id: + receive RegisterClientReply -> idle + + +shutdown-cancelled: + send SaveYourselfDone -> idle + + +idle: [Undoes any freeze of interaction with user.] + receive Die -> die + receive SaveYourself -> freeze-interaction + send GetProperties -> idle + receive GetPropertiesReply -> idle + send SetProperties -> idle + send DeleteProperties -> idle + send ConnectionClosed -> connection-closed + send SaveYourselfRequest -> idle + + + +die: + send ConnectionClosed -> connection-closed + + +freeze-interaction: + freeze interaction with user -> save-yourself + + +save-yourself: + receive ShutdownCancelled -> shutdown-cancelled + send SetProperties -> save-yourself + send DeleteProperties -> save-yourself + send GetProperties -> save-yourself + receive GetPropertiesReply -> save-yourself + send InteractRequest -> interact-request + send SaveYourselfPhase2Request -> waiting-for-phase2 + +save-yourself: + if shutdown mode: + send SaveYourselfDone -> save-yourself-done + otherwise: + send SaveYourselfDone -> idle + + +waiting-for-phase2: + receive ShutdownCancelled -> shutdown-cancelled + receive SaveYourselfPhase2 -> phase2 + + +phase2: + receive ShutdownCancelled -> shutdown-cancelled + send SetProperties -> save-yourself + send DeleteProperties -> save-yourself + send GetProperties -> save-yourself + receive GetPropertiesReply -> save-yourself + send InteractRequest -> interact-request (errors only) + if shutdown mode: + send SaveYourselfDone -> save-yourself-done + otherwise: + send SaveYourselfDone -> idle + + +interact-request: + receive Interact -> interact + receive ShutdownCancelled -> shutdown-cancelled + + +interact: + send InteractDone -> save-yourself + receive ShutdownCancelled -> shutdown-cancelled + + +save-yourself-done: (changing state is forbidden) + receive SaveComplete -> idle + receive Die -> die + receive ShutdownCancelled -> idle + + +connection-closed: + client stops participating in session + + + +Session Manager State Diagram + + +start: + receive ProtocolSetup -> protocol-setup + + +protocol-setup: + send ProtocolSetupReply -> register + + +register: + receive RegisterClient -> acknowledge-register + + + +acknowledge-register: + send RegisterClientReply -> idle + + + +idle: + receive SetProperties -> idle + receive DeleteProperties -> idle + receive ConnectionClosed -> start + receive GetProperties -> get-properties + receive SaveYourselfRequest -> save-yourself + send SaveYourself -> saving-yourself + + + +save-yourself: + send SaveYourself -> saving-yourself + + + +get-properties: + send GetPropertiesReply -> idle + + + +saving-get-properties: + send GetPropertiesReply -> saving-yourself + + + +saving-yourself: + receive InteractRequest -> saving-yourself + send Interact -> saving-yourself + send ShutdownCancelled -> idle + receive InteractDone -> saving-yourself + receive SetProperties -> saving-yourself + receive DeleteProperties -> saving-yourself + receive GetProperties -> saving-get-properties + receive SaveYourselfPhase2Request -> start-phase2 + receive SaveYourselfDone -> save-yourself-done + + + +start-phase2: + If all clients have sent either SaveYourselfPhase2Request or SaveYourselfDone: + send SaveYourselfPhase2 -> phase2 + else + -> saving-yourself + + + +phase2: + receive InteractRequest -> saving-yourself + send Interact -> saving-yourself + send ShutdownCancelled -> idle + receive InteractDone -> saving-yourself + receive SetProperties -> saving-yourself + receive DeleteProperties -> saving-yourself + receive GetProperties -> saving-get-properties + receive SaveYourselfDone -> save-yourself-done + + + +save-yourself-done: + If all clients are saved: + If shutting down: + send Die -> die + otherwise + send SaveComplete -> idle + + If some clients are not saved: + -> saving-yourself + + + +die: + SM stops accepting connections + + + + + +Protocol Encoding + +Types + + + + + + + + BOOL + + + + + 0 + False + + + 1 + True + + + + + + + + + + + + INTERACT_STYLE + + + + + 0 + None + + + 1 + Errors + + + 2 + Any + + + + + + + + + + + + DIALOG_TYPE + + + + + 0 + Error + + + 1 + Normal + + + + + + + + + + + + SAVE_TYPE + + + + + 0 + Global + + + 1 + Local + + + 2 + Both + + + + + + + + + + + + + ARRAY8 + + + + + 4 + CARD32 + length + + + n + ListofCARD8, the array + p = pad (4 + n, 8) + + + 2 + Both + + + + + + + + + + + + + LISTofARRAY8 + + + + + 4 + CARD32 + count + + + 4 + + unused + + + a + ARRAY8 + first array + + + b + ARRAY8 + second array + + + . + + + + + . + + + + + . + + + + + q + ARRAY8 + last array + + + + + + + + + + + + + PROPERTY + + + + + a + ARRAY8 + name + + + b + ARRAY8 + type (XPCS encoded in Latin-1, case sensitive) + + + c + LISTofARRAY8 + values + + + + + + + + + + + + + LISTofPROPERTY + + + + + 4 + CARD32 + count + + + 4 + + unused + + + a + PROPERTY + first property + + + b + PROPERTY + second property + + + . + + + + + . + + + + + . + + + + + q + PROPERTY + last property + + + + + + + + +Messages +XSMP is a sub-protocol of ICE. The major opcode is assigned at run-time by ICE and is represented here by '?'. + +To start the XSMP protocol, the client sends the server an ICE ProtocolSetup message. The protocol-name field should be specified as "XSMP", the major version of the protocol is 1, the minor version is 0. These values may change if the protocol is revised. The minor version number will be incremented if the change is compatible, otherwise the major version number will be incremented. + +In ProtocolReply message sent by the session manager, the XSMP protocol defines the vendor parameter as product identification of the session manager, and defines the release parameter as the software release identification of the session manager. The session manager should supply this information in the ICE ProtocolReply message. + + + + + + + + + RegisterClient + + + + + 1 + ? + XSMP + + + 1 + 1 + opcode + + + 2 + + unused + + + 4 + a/8 + length of remaining data in 8-byte units + + + a + ARRAY8 + previous-ID + + + + + + + + + + + + + RegisterClientReply + + + + + 1 + ? + XSMP + + + 1 + 2 + opcode + + + 2 + + unused + + + 4 + a/8 + length of remaining data in 8-byte units + + + a + ARRAY8 + client-ID + + + + + + + + + + + + + SaveYourself + + + + + 1 + ? + XSMP + + + 1 + 3 + opcode + + + 2 + + unused + + + 4 + 1 + length of remaining data in 8-byte units + + + 1 + SAVE_TYPE + type + + + 1 + BOOL + shutdown + + + 1 + INTERACT_STYLE + interact-style + + + 1 + BOOL + fast + + + 4 + + unused + + + + + + + + + + + + + SaveYourselfRequest + + + + + 1 + ? + XSMP + + + 1 + 4 + opcode + + + 2 + + unused + + + 4 + 1 + length of remainning data in 8-byte units + + + 1 + SAVE_TYPE + type + + + 1 + BOOL + shutdown + + + 1 + INTERACT_STYLE + interact-style + + + 1 + BOOL + fast + + + 3 + + unused + + + + + + + + + + + + + InteractRequest + + + + + 1 + ? + XSMP + + + 1 + 5 + opcode + + + 1 + DIALOG_TYPE + dialog type + + + 1 + + unused + + + 4 + 0 + length of remaining data in 8-byte units + + + + + + + + + + + + + Interact + + + + + 1 + ? + XSMP + + + 1 + 6 + opcode + + + 2 + + unused + + + 4 + 0 + length of remaining data in 8-byte units + + + + + + + + + + + + + InteractDone + + + + + 1 + ? + XSMP + + + 1 + 7 + opcode + + + 1 + BOOL + cancel-shutdown + + + 1 + + unused + + + + + + + + + + + + + + InteractDone + + + + + 1 + ? + XSMP + + + 1 + 7 + opcode + + + 1 + BOOL + cancel-shutdown + + + 1 + + unused + + + 4 + 0 + length of remaining data in 8-byte units + + + + + + + + + + + + + SaveYourselfDone + + + + + 1 + ? + XSMP + + + 1 + 8 + opcode + + + 1 + BOOL + success + + + 1 + + unused + + + 4 + 0 + length of remaining data in 8-byte units + + + + + + + + + + + + + Die + + + + + 1 + ? + XSMP + + + 1 + 9 + opcode + + + 1 + + unused + + + 4 + 0 + length of remaining data in 8-byte units + + + + + + + + + + + + + ShutdownCancelled + + + + + 1 + ? + XSMP + + + 1 + 10 + opcode + + + 2 + + unused + + + 4 + 0 + length of remaining data in 8-byte units + + + + + + + + + + + + + ConnectionClosed + + + + + 1 + ? + XSMP + + + 1 + 11 + opcode + + + 2 + + unused + + + 4 + a/8 + length of remaining data in 8-byte units + + + a + LISTofARRAY8 + reason + + + + + + + + + + + + + SetProperties + + + + + 1 + ? + XSMP + + + 1 + 12 + opcode + + + 2 + + unused + + + 4 + a/8 + length of remaining data in 8-byte units + + + a + LISTofPROPERTY + properties + + + + + + + + + + + + + DeleteProperties + + + + + 1 + ? + XSMP + + + 1 + 13 + opcode + + + 2 + + unused + + + 4 + a/8 + length of remaining data in 8-byte units + + + a + LISTofPROPERTY + properties + + + + + + + + + + + + + GetProperties + + + + + 1 + ? + XSMP + + + 1 + 14 + opcode + + + 2 + + unused + + + 4 + 0 + length of remaining data in 8-byte units + + + + + + + + + + + + + GetPropertiesReply + + + + + 1 + ? + XSMP + + + 1 + 15 + opcode + + + 2 + + unused + + + 4 + a/8 + length of remaining data in 8-byte units + + + a + LISTofPROPERTY + properties + + + + + + + + + + + + + SaveYourselfPhase2Request + + + + + 1 + ? + XSMP + + + 1 + 16 + opcode + + + 2 + + unused + + + 4 + 0 + length of remaining data in 8-byte units + + + + + + + + + + + + + SaveYourselfPhase2 + + + + + 1 + ? + XSMP + + + 1 + 17 + opcode + + + 2 + + unused + + + 4 + 0 + length of remaining data in 8-byte units + + + + + + + + + + + + + SaveComplete + + + + + 1 + ? + XSMP + + + 1 + 18 + opcode + + + 2 + + unused + + + 4 + 0 + length of remaining data in 8-byte units + + + + + + + + + +Predefined Properties +All property values are stored in a LISTofARRAY8. If the type of the property is CARD8, the value is stored as a LISTofARRAY8 with one ARRAY8 that is one byte long. That single byte contains the CARD8. If the type of the property is ARRAY8, the value is stored in the first element of a single element LISTofARRAY8. + +The required properties must be set each time a client connects with the SM. The properties must be set after the client sends RegisterClient and before the client sends SaveYourselfDone Otherwise, the behavior of the session manager is not defined. + +Clients may set, get, and delete nonstandard properties. The lifetime of stored properties does not extend into subsequent sessions. + + + + + + + + + + Name + Type + Posix Type + Required? + + + + + CloneCommand + OS-specific + LISTofARRAY8 + Yes + + + CurrentDirectory + OS-specific + ARRAY8 + No + + + DiscardCommand + OS-specific + LISTofARRAY8 + No* + + + Environment + OS-specific + LISTofARRAY8 + No + + + ProcessID + OS-specific + ARRAY8 + No + + + Program + OS-specific + ARRAY8 + Yes + + + RestartCommand + OS-specific + LISTofARRAY8 + Yes + + + ResignCommand + OS-specific + LISTofARRAY8 + No + + + RestartStyleHint + CARD8 + CARD8 + No + + + ShutdownCommand + OS-specific + LISTofARRAY8 + No + + + UserID + ARRAY8 + ARRAY8 + Yes + + + + + +* Required if any state is stored in an external repository (e.g., state file). + + + + CloneCommand + This is like the RestartCommand except it restarts a copy of the application. The only difference is that the application doesn't supply its client id at register time. On POSIX systems the type should be a LISTofARRAY8. + + + CurrentDirectory + On POSIX-based systems specifies the value of the current directory that needs to be set up prior to starting the program and should be of type ARRAY8. + + + DiscardCommand + The discard command contains a command that when delivered to the host that the client is running on (determined from the connection), will cause it to discard any information about the current state. If this command is not specified, the SM will assume that all of the client's state is encoded in the Restart­Command On POSIX systems the type should be LISTofARRAY8. + + + Environment + On POSIX based systems, this will be of type LISTofARRAY8 where the ARRAY8s alternate between environment variable name and environment variable value. + + + ProcessID + This specifies an OS-specific identifier for the process. On POSIX systems this should of type ARRAY8 and contain the return value of getpid() turned into a Latin-1 (decimal) string. + + + Program + The name of the program that is running. On POSIX systems this should be the first parameter passed to execve and should be of type ARRAY8. + + + RestartCommand + The restart command contains a command that when delivered to the host that the client is running on (determined from the connection), will cause the client to restart in its current state. On POSIX-based systems this is of type LISTofARRAY8 and each of the elements in the array represents an element in the argv array. This restart command should ensure that the client restarts with the specified client-ID. + + + ResignCommand + A client that sets the RestartStyleHint to RestartAnyway uses this property to specify a command that undoes the effect of the client and removes any saved state. + A user runs xmodmap. xmodmap registers with the SM, sets Restart­Style­Hint to Restart­Anyway and then terminates. In order to allow the SM (at the user's request) to undo this, xmodmap would register a Resign­Command that undoes the effects of the xmodmap. + + + + RestartStyleHint + If the RestartStyleHint property is present, it will contain the style of restarting the client prefers. If this flag isn't specified, RestartIfRunning is assumed. The possible values are as follows: + + + + + + + + Name + Value + + + .TH + + + + + + RestartIfRunning + 0 + + + RestartAnyway + 1 + + + RestartImmediately + 2 + + + RestartNever + 3 + + + + + +The RestartIfRunning style is used in the usual case. The client should be restarted in the next session if it is connected to the session manager at the end of the current session. + +The RestartAnyway style is used to tell the SM that the application should be restarted in the next session even if it exits before the current session is terminated. It should be noted that this is only a hint and the SM will follow the policies specified by its users in determining what applications to restart. + + This can be specified by a client which supports (as MS-Windows clients do) a means for the user to indicate while exiting that restarting is desired. It can also be used for clients that spawn other clients and then go away, but which want to be restarted. + +A client that uses RestartAnyway should also set the ResignCommand and ShutdownCommand properties to commands that undo the state of the client after it exits. + +The RestartImmediately style is like RestartAnyway but in addition, the client is meant to run continuously. If the client exits, the SM should try to restart it in the current session. +It would be wise to sanity-check the frequency which which RestartImmediately clients are restarted, to avoid a sick client being restarted continuously. +The RestartNever style specifies that the client does not wish to be restarted in the next session. + This should be used rarely, if at all. It will cause the client to be silently left out of sessions when they are restarted and will probably be confusing to users. + + + + + ShutdownCommand + This command is executed at shutdown time to clean up after a client that is no longer running but retained its state by setting RestartStyleHint to RestartAnyway The command must not remove any saved state as the client is still part of the session. +A client is run at start up time that turns on a camera. This client then exits. At session shutdown, the user wants the camera turned off. This client would set the Restart­Style­Hint to Restart­Anyway and would register a Shutdown­Command that would turn off the camera. + + + + UserID + Specifies the user's ID. On POSIX-based systems this will contain the the user's name (the pw_name field of struct passwd). + + + + + -- cgit v1.2.1