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diff --git a/gdb/doc/gdb.info-8 b/gdb/doc/gdb.info-8 new file mode 100644 index 00000000000..8d2bf47cc97 --- /dev/null +++ b/gdb/doc/gdb.info-8 @@ -0,0 +1,1308 @@ +This is Info file ./gdb.info, produced by Makeinfo version 1.68 from +the input file gdb.texinfo. + +START-INFO-DIR-ENTRY +* Gdb: (gdb). The GNU debugger. +END-INFO-DIR-ENTRY + This file documents the GNU debugger GDB. + + This is the Seventh Edition, February 1999, of `Debugging with GDB: +the GNU Source-Level Debugger' for GDB Version 4.18. + + Copyright (C) 1988-1999 Free Software Foundation, Inc. + + Permission is granted to make and distribute verbatim copies of this +manual provided the copyright notice and this permission notice are +preserved on all copies. + + Permission is granted to copy and distribute modified versions of +this manual under the conditions for verbatim copying, provided also +that the entire resulting derived work is distributed under the terms +of a permission notice identical to this one. + + Permission is granted to copy and distribute translations of this +manual into another language, under the above conditions for modified +versions. + + +File: gdb.info, Node: Emacs, Next: GDB Bugs, Prev: Sequences, Up: Top + +Using GDB under GNU Emacs +************************* + + A special interface allows you to use GNU Emacs to view (and edit) +the source files for the program you are debugging with GDB. + + To use this interface, use the command `M-x gdb' in Emacs. Give the +executable file you want to debug as an argument. This command starts +GDB as a subprocess of Emacs, with input and output through a newly +created Emacs buffer. + + Using GDB under Emacs is just like using GDB normally except for two +things: + + * All "terminal" input and output goes through the Emacs buffer. + + This applies both to GDB commands and their output, and to the input +and output done by the program you are debugging. + + This is useful because it means that you can copy the text of +previous commands and input them again; you can even use parts of the +output in this way. + + All the facilities of Emacs' Shell mode are available for interacting +with your program. In particular, you can send signals the usual +way--for example, `C-c C-c' for an interrupt, `C-c C-z' for a stop. + + * GDB displays source code through Emacs. + + Each time GDB displays a stack frame, Emacs automatically finds the +source file for that frame and puts an arrow (`=>') at the left margin +of the current line. Emacs uses a separate buffer for source display, +and splits the screen to show both your GDB session and the source. + + Explicit GDB `list' or search commands still produce output as +usual, but you probably have no reason to use them from Emacs. + + *Warning:* If the directory where your program resides is not your + current directory, it can be easy to confuse Emacs about the + location of the source files, in which case the auxiliary display + buffer does not appear to show your source. GDB can find programs + by searching your environment's `PATH' variable, so the GDB input + and output session proceeds normally; but Emacs does not get + enough information back from GDB to locate the source files in + this situation. To avoid this problem, either start GDB mode from + the directory where your program resides, or specify an absolute + file name when prompted for the `M-x gdb' argument. + + A similar confusion can result if you use the GDB `file' command to + switch to debugging a program in some other location, from an + existing GDB buffer in Emacs. + + By default, `M-x gdb' calls the program called `gdb'. If you need +to call GDB by a different name (for example, if you keep several +configurations around, with different names) you can set the Emacs +variable `gdb-command-name'; for example, + + (setq gdb-command-name "mygdb") + +(preceded by `ESC ESC', or typed in the `*scratch*' buffer, or in your +`.emacs' file) makes Emacs call the program named "`mygdb'" instead. + + In the GDB I/O buffer, you can use these special Emacs commands in +addition to the standard Shell mode commands: + +`C-h m' + Describe the features of Emacs' GDB Mode. + +`M-s' + Execute to another source line, like the GDB `step' command; also + update the display window to show the current file and location. + +`M-n' + Execute to next source line in this function, skipping all function + calls, like the GDB `next' command. Then update the display window + to show the current file and location. + +`M-i' + Execute one instruction, like the GDB `stepi' command; update + display window accordingly. + +`M-x gdb-nexti' + Execute to next instruction, using the GDB `nexti' command; update + display window accordingly. + +`C-c C-f' + Execute until exit from the selected stack frame, like the GDB + `finish' command. + +`M-c' + Continue execution of your program, like the GDB `continue' + command. + + *Warning:* In Emacs v19, this command is `C-c C-p'. + +`M-u' + Go up the number of frames indicated by the numeric argument + (*note Numeric Arguments: (Emacs)Arguments.), like the GDB `up' + command. + + *Warning:* In Emacs v19, this command is `C-c C-u'. + +`M-d' + Go down the number of frames indicated by the numeric argument, + like the GDB `down' command. + + *Warning:* In Emacs v19, this command is `C-c C-d'. + +`C-x &' + Read the number where the cursor is positioned, and insert it at + the end of the GDB I/O buffer. For example, if you wish to + disassemble code around an address that was displayed earlier, + type `disassemble'; then move the cursor to the address display, + and pick up the argument for `disassemble' by typing `C-x &'. + + You can customize this further by defining elements of the list + `gdb-print-command'; once it is defined, you can format or + otherwise process numbers picked up by `C-x &' before they are + inserted. A numeric argument to `C-x &' indicates that you wish + special formatting, and also acts as an index to pick an element + of the list. If the list element is a string, the number to be + inserted is formatted using the Emacs function `format'; otherwise + the number is passed as an argument to the corresponding list + element. + + In any source file, the Emacs command `C-x SPC' (`gdb-break') tells +GDB to set a breakpoint on the source line point is on. + + If you accidentally delete the source-display buffer, an easy way to +get it back is to type the command `f' in the GDB buffer, to request a +frame display; when you run under Emacs, this recreates the source +buffer if necessary to show you the context of the current frame. + + The source files displayed in Emacs are in ordinary Emacs buffers +which are visiting the source files in the usual way. You can edit the +files with these buffers if you wish; but keep in mind that GDB +communicates with Emacs in terms of line numbers. If you add or delete +lines from the text, the line numbers that GDB knows cease to +correspond properly with the code. + + +File: gdb.info, Node: GDB Bugs, Next: Formatting Documentation, Prev: Emacs, Up: Top + +Reporting Bugs in GDB +********************* + + Your bug reports play an essential role in making GDB reliable. + + Reporting a bug may help you by bringing a solution to your problem, +or it may not. But in any case the principal function of a bug report +is to help the entire community by making the next version of GDB work +better. Bug reports are your contribution to the maintenance of GDB. + + In order for a bug report to serve its purpose, you must include the +information that enables us to fix the bug. + +* Menu: + +* Bug Criteria:: Have you found a bug? +* Bug Reporting:: How to report bugs + + +File: gdb.info, Node: Bug Criteria, Next: Bug Reporting, Prev: GDB Bugs, Up: GDB Bugs + +Have you found a bug? +===================== + + If you are not sure whether you have found a bug, here are some +guidelines: + + * If the debugger gets a fatal signal, for any input whatever, that + is a GDB bug. Reliable debuggers never crash. + + * If GDB produces an error message for valid input, that is a bug. + (Note that if you're cross debugging, the problem may also be + somewhere in the connection to the target.) + + * If GDB does not produce an error message for invalid input, that + is a bug. However, you should note that your idea of "invalid + input" might be our idea of "an extension" or "support for + traditional practice". + + * If you are an experienced user of debugging tools, your suggestions + for improvement of GDB are welcome in any case. + + +File: gdb.info, Node: Bug Reporting, Prev: Bug Criteria, Up: GDB Bugs + +How to report bugs +================== + + A number of companies and individuals offer support for GNU products. +If you obtained GDB from a support organization, we recommend you +contact that organization first. + + You can find contact information for many support companies and +individuals in the file `etc/SERVICE' in the GNU Emacs distribution. + + In any event, we also recommend that you send bug reports for GDB to +this addresses: + + bug-gdb@prep.ai.mit.edu + + *Do not send bug reports to `info-gdb', or to `help-gdb', or to any +newsgroups.* Most users of GDB do not want to receive bug reports. +Those that do have arranged to receive `bug-gdb'. + + The mailing list `bug-gdb' has a newsgroup `gnu.gdb.bug' which +serves as a repeater. The mailing list and the newsgroup carry exactly +the same messages. Often people think of posting bug reports to the +newsgroup instead of mailing them. This appears to work, but it has one +problem which can be crucial: a newsgroup posting often lacks a mail +path back to the sender. Thus, if we need to ask for more information, +we may be unable to reach you. For this reason, it is better to send +bug reports to the mailing list. + + As a last resort, send bug reports on paper to: + + GNU Debugger Bugs + Free Software Foundation Inc. + 59 Temple Place - Suite 330 + Boston, MA 02111-1307 + USA + + The fundamental principle of reporting bugs usefully is this: +*report all the facts*. If you are not sure whether to state a fact or +leave it out, state it! + + Often people omit facts because they think they know what causes the +problem and assume that some details do not matter. Thus, you might +assume that the name of the variable you use in an example does not +matter. Well, probably it does not, but one cannot be sure. Perhaps +the bug is a stray memory reference which happens to fetch from the +location where that name is stored in memory; perhaps, if the name were +different, the contents of that location would fool the debugger into +doing the right thing despite the bug. Play it safe and give a +specific, complete example. That is the easiest thing for you to do, +and the most helpful. + + Keep in mind that the purpose of a bug report is to enable us to fix +the bug. It may be that the bug has been reported previously, but +neither you nor we can know that unless your bug report is complete and +self-contained. + + Sometimes people give a few sketchy facts and ask, "Does this ring a +bell?" Those bug reports are useless, and we urge everyone to *refuse +to respond to them* except to chide the sender to report bugs properly. + + To enable us to fix the bug, you should include all these things: + + * The version of GDB. GDB announces it if you start with no + arguments; you can also print it at any time using `show version'. + + Without this, we will not know whether there is any point in + looking for the bug in the current version of GDB. + + * The type of machine you are using, and the operating system name + and version number. + + 1. What compiler (and its version) was used to compile GDB--e.g. + "gcc-2.8.1". + + * What compiler (and its version) was used to compile the program + you are debugging--e.g. "gcc-2.8.1", or "HP92453-01 A.10.32.03 HP + C Compiler". For GCC, you can say `gcc --version' to get this + information; for other compilers, see the documentation for those + compilers. + + * The command arguments you gave the compiler to compile your + example and observe the bug. For example, did you use `-O'? To + guarantee you will not omit something important, list them all. A + copy of the Makefile (or the output from make) is sufficient. + + If we were to try to guess the arguments, we would probably guess + wrong and then we might not encounter the bug. + + * A complete input script, and all necessary source files, that will + reproduce the bug. + + * A description of what behavior you observe that you believe is + incorrect. For example, "It gets a fatal signal." + + Of course, if the bug is that GDB gets a fatal signal, then we + will certainly notice it. But if the bug is incorrect output, we + might not notice unless it is glaringly wrong. You might as well + not give us a chance to make a mistake. + + Even if the problem you experience is a fatal signal, you should + still say so explicitly. Suppose something strange is going on, + such as, your copy of GDB is out of synch, or you have encountered + a bug in the C library on your system. (This has happened!) Your + copy might crash and ours would not. If you told us to expect a + crash, then when ours fails to crash, we would know that the bug + was not happening for us. If you had not told us to expect a + crash, then we would not be able to draw any conclusion from our + observations. + + 2. If you wish to suggest changes to the GDB source, send us context + diffs. If you even discuss something in the GDB source, refer to + it by context, not by line number. + + The line numbers in our development sources will not match those + in your sources. Your line numbers would convey no useful + information to us. + + Here are some things that are not necessary: + + * A description of the envelope of the bug. + + Often people who encounter a bug spend a lot of time investigating + which changes to the input file will make the bug go away and which + changes will not affect it. + + This is often time consuming and not very useful, because the way + we will find the bug is by running a single example under the + debugger with breakpoints, not by pure deduction from a series of + examples. We recommend that you save your time for something else. + + Of course, if you can find a simpler example to report *instead* + of the original one, that is a convenience for us. Errors in the + output will be easier to spot, running under the debugger will take + less time, and so on. + + However, simplification is not vital; if you do not want to do + this, report the bug anyway and send us the entire test case you + used. + + * A patch for the bug. + + A patch for the bug does help us if it is a good one. But do not + omit the necessary information, such as the test case, on the + assumption that a patch is all we need. We might see problems + with your patch and decide to fix the problem another way, or we + might not understand it at all. + + Sometimes with a program as complicated as GDB it is very hard to + construct an example that will make the program follow a certain + path through the code. If you do not send us the example, we will + not be able to construct one, so we will not be able to verify + that the bug is fixed. + + And if we cannot understand what bug you are trying to fix, or why + your patch should be an improvement, we will not install it. A + test case will help us to understand. + + * A guess about what the bug is or what it depends on. + + Such guesses are usually wrong. Even we cannot guess right about + such things without first using the debugger to find the facts. + + +File: gdb.info, Node: Command Line Editing, Next: Using History Interactively, Prev: Formatting Documentation, Up: Top + +Command Line Editing +******************** + + This chapter describes the basic features of the GNU command line +editing interface. + +* Menu: + +* Introduction and Notation:: Notation used in this text. +* Readline Interaction:: The minimum set of commands for editing a line. +* Readline Init File:: Customizing Readline from a user's view. +* Bindable Readline Commands:: A description of most of the Readline commands + available for binding +* Readline vi Mode:: A short description of how to make Readline + behave like the vi editor. + + +File: gdb.info, Node: Introduction and Notation, Next: Readline Interaction, Up: Command Line Editing + +Introduction to Line Editing +============================ + + The following paragraphs describe the notation used to represent +keystrokes. + + The text <C-k> is read as `Control-K' and describes the character +produced when the <k> key is pressed while the Control key is depressed. + + The text <M-k> is read as `Meta-K' and describes the character +produced when the meta key (if you have one) is depressed, and the <k> +key is pressed. If you do not have a meta key, the identical keystroke +can be generated by typing <ESC> first, and then typing <k>. Either +process is known as "metafying" the <k> key. + + The text <M-C-k> is read as `Meta-Control-k' and describes the +character produced by "metafying" <C-k>. + + In addition, several keys have their own names. Specifically, +<DEL>, <ESC>, <LFD>, <SPC>, <RET>, and <TAB> all stand for themselves +when seen in this text, or in an init file (*note Readline Init +File::.). + + +File: gdb.info, Node: Readline Interaction, Next: Readline Init File, Prev: Introduction and Notation, Up: Command Line Editing + +Readline Interaction +==================== + + Often during an interactive session you type in a long line of text, +only to notice that the first word on the line is misspelled. The +Readline library gives you a set of commands for manipulating the text +as you type it in, allowing you to just fix your typo, and not forcing +you to retype the majority of the line. Using these editing commands, +you move the cursor to the place that needs correction, and delete or +insert the text of the corrections. Then, when you are satisfied with +the line, you simply press <RETURN>. You do not have to be at the end +of the line to press <RETURN>; the entire line is accepted regardless +of the location of the cursor within the line. + +* Menu: + +* Readline Bare Essentials:: The least you need to know about Readline. +* Readline Movement Commands:: Moving about the input line. +* Readline Killing Commands:: How to delete text, and how to get it back! +* Readline Arguments:: Giving numeric arguments to commands. +* Searching:: Searching through previous lines. + + +File: gdb.info, Node: Readline Bare Essentials, Next: Readline Movement Commands, Up: Readline Interaction + +Readline Bare Essentials +------------------------ + + In order to enter characters into the line, simply type them. The +typed character appears where the cursor was, and then the cursor moves +one space to the right. If you mistype a character, you can use your +erase character to back up and delete the mistyped character. + + Sometimes you may miss typing a character that you wanted to type, +and not notice your error until you have typed several other +characters. In that case, you can type <C-b> to move the cursor to the +left, and then correct your mistake. Afterwards, you can move the +cursor to the right with <C-f>. + + When you add text in the middle of a line, you will notice that +characters to the right of the cursor are `pushed over' to make room +for the text that you have inserted. Likewise, when you delete text +behind the cursor, characters to the right of the cursor are `pulled +back' to fill in the blank space created by the removal of the text. A +list of the basic bare essentials for editing the text of an input line +follows. + +<C-b> + Move back one character. + +<C-f> + Move forward one character. + +<DEL> + Delete the character to the left of the cursor. + +<C-d> + Delete the character underneath the cursor. + +Printing characters + Insert the character into the line at the cursor. + +<C-_> + Undo the last editing command. You can undo all the way back to an + empty line. + + +File: gdb.info, Node: Readline Movement Commands, Next: Readline Killing Commands, Prev: Readline Bare Essentials, Up: Readline Interaction + +Readline Movement Commands +-------------------------- + + The above table describes the most basic possible keystrokes that +you need in order to do editing of the input line. For your +convenience, many other commands have been added in addition to <C-b>, +<C-f>, <C-d>, and <DEL>. Here are some commands for moving more rapidly +about the line. + +<C-a> + Move to the start of the line. + +<C-e> + Move to the end of the line. + +<M-f> + Move forward a word, where a word is composed of letters and + digits. + +<M-b> + Move backward a word. + +<C-l> + Clear the screen, reprinting the current line at the top. + + Notice how <C-f> moves forward a character, while <M-f> moves +forward a word. It is a loose convention that control keystrokes +operate on characters while meta keystrokes operate on words. + + +File: gdb.info, Node: Readline Killing Commands, Next: Readline Arguments, Prev: Readline Movement Commands, Up: Readline Interaction + +Readline Killing Commands +------------------------- + + "Killing" text means to delete the text from the line, but to save +it away for later use, usually by "yanking" (re-inserting) it back into +the line. If the description for a command says that it `kills' text, +then you can be sure that you can get the text back in a different (or +the same) place later. + + When you use a kill command, the text is saved in a "kill-ring". +Any number of consecutive kills save all of the killed text together, so +that when you yank it back, you get it all. The kill ring is not line +specific; the text that you killed on a previously typed line is +available to be yanked back later, when you are typing another line. + + Here is the list of commands for killing text. + +<C-k> + Kill the text from the current cursor position to the end of the + line. + +<M-d> + Kill from the cursor to the end of the current word, or if between + words, to the end of the next word. + +<M-DEL> + Kill from the cursor the start of the previous word, or if between + words, to the start of the previous word. + +<C-w> + Kill from the cursor to the previous whitespace. This is + different than <M-DEL> because the word boundaries differ. + + Here is how to "yank" the text back into the line. Yanking means to +copy the most-recently-killed text from the kill buffer. + +<C-y> + Yank the most recently killed text back into the buffer at the + cursor. + +<M-y> + Rotate the kill-ring, and yank the new top. You can only do this + if the prior command is <C-y> or <M-y>. + + +File: gdb.info, Node: Readline Arguments, Next: Searching, Prev: Readline Killing Commands, Up: Readline Interaction + +Readline Arguments +------------------ + + You can pass numeric arguments to Readline commands. Sometimes the +argument acts as a repeat count, other times it is the sign of the +argument that is significant. If you pass a negative argument to a +command which normally acts in a forward direction, that command will +act in a backward direction. For example, to kill text back to the +start of the line, you might type `M-- C-k'. + + The general way to pass numeric arguments to a command is to type +meta digits before the command. If the first `digit' typed is a minus +sign (<->), then the sign of the argument will be negative. Once you +have typed one meta digit to get the argument started, you can type the +remainder of the digits, and then the command. For example, to give +the <C-d> command an argument of 10, you could type `M-1 0 C-d'. + + +File: gdb.info, Node: Searching, Prev: Readline Arguments, Up: Readline Interaction + +Searching for Commands in the History +------------------------------------- + + Readline provides commands for searching through the command history +for lines containing a specified string. There are two search modes: +INCREMENTAL and NON-INCREMENTAL. + + Incremental searches begin before the user has finished typing the +search string. As each character of the search string is typed, +Readline displays the next entry from the history matching the string +typed so far. An incremental search requires only as many characters +as needed to find the desired history entry. The <ESC> character is +used to terminate an incremental search. <C-j> will also terminate the +search. <C-g> will abort an incremental search and restore the +original line. When the search is terminated, the history entry +containing the search string becomes the current line. To find other +matching entries in the history list, type <C-s> or <C-r> as +appropriate. This will search backward or forward in the history for +the next entry matching the search string typed so far. Any other key +sequence bound to a Readline command will terminate the search and +execute that command. For instance, a <RET> will terminate the search +and accept the line, thereby executing the command from the history +list. + + Non-incremental searches read the entire search string before +starting to search for matching history lines. The search string may be +typed by the user or be part of the contents of the current line. + + +File: gdb.info, Node: Readline Init File, Next: Bindable Readline Commands, Prev: Readline Interaction, Up: Command Line Editing + +Readline Init File +================== + + Although the Readline library comes with a set of `emacs'-like +keybindings installed by default, it is possible to use a different set +of keybindings. Any user can customize programs that use Readline by +putting commands in an "inputrc" file in his home directory. The name +of this file is taken from the value of the environment variable +`INPUTRC'. If that variable is unset, the default is `~/.inputrc'. + + When a program which uses the Readline library starts up, the init +file is read, and the key bindings are set. + + In addition, the `C-x C-r' command re-reads this init file, thus +incorporating any changes that you might have made to it. + +* Menu: + +* Readline Init File Syntax:: Syntax for the commands in the inputrc file. + +* Conditional Init Constructs:: Conditional key bindings in the inputrc file. + +* Sample Init File:: An example inputrc file. + + +File: gdb.info, Node: Readline Init File Syntax, Next: Conditional Init Constructs, Up: Readline Init File + +Readline Init File Syntax +------------------------- + + There are only a few basic constructs allowed in the Readline init +file. Blank lines are ignored. Lines beginning with a `#' are +comments. Lines beginning with a `$' indicate conditional constructs +(*note Conditional Init Constructs::.). Other lines denote variable +settings and key bindings. + +Variable Settings + You can modify the run-time behavior of Readline by altering the + values of variables in Readline using the `set' command within the + init file. Here is how to change from the default Emacs-like key + binding to use `vi' line editing commands: + + set editing-mode vi + + A great deal of run-time behavior is changeable with the following + variables. + + `bell-style' + Controls what happens when Readline wants to ring the + terminal bell. If set to `none', Readline never rings the + bell. If set to `visible', Readline uses a visible bell if + one is available. If set to `audible' (the default), + Readline attempts to ring the terminal's bell. + + `comment-begin' + The string to insert at the beginning of the line when the + `insert-comment' command is executed. The default value is + `"#"'. + + `completion-ignore-case' + If set to `on', Readline performs filename matching and + completion in a case-insensitive fashion. The default value + is `off'. + + `completion-query-items' + The number of possible completions that determines when the + user is asked whether he wants to see the list of + possibilities. If the number of possible completions is + greater than this value, Readline will ask the user whether + or not he wishes to view them; otherwise, they are simply + listed. The default limit is `100'. + + `convert-meta' + If set to `on', Readline will convert characters with the + eighth bit set to an ASCII key sequence by stripping the + eighth bit and prepending an <ESC> character, converting them + to a meta-prefixed key sequence. The default value is `on'. + + `disable-completion' + If set to `On', Readline will inhibit word completion. + Completion characters will be inserted into the line as if + they had been mapped to `self-insert'. The default is `off'. + + `editing-mode' + The `editing-mode' variable controls which default set of key + bindings is used. By default, Readline starts up in Emacs + editing mode, where the keystrokes are most similar to Emacs. + This variable can be set to either `emacs' or `vi'. + + `enable-keypad' + When set to `on', Readline will try to enable the application + keypad when it is called. Some systems need this to enable + the arrow keys. The default is `off'. + + `expand-tilde' + If set to `on', tilde expansion is performed when Readline + attempts word completion. The default is `off'. + + `horizontal-scroll-mode' + This variable can be set to either `on' or `off'. Setting it + to `on' means that the text of the lines being edited will + scroll horizontally on a single screen line when they are + longer than the width of the screen, instead of wrapping onto + a new screen line. By default, this variable is set to `off'. + + `keymap' + Sets Readline's idea of the current keymap for key binding + commands. Acceptable `keymap' names are `emacs', + `emacs-standard', `emacs-meta', `emacs-ctlx', `vi', + `vi-command', and `vi-insert'. `vi' is equivalent to + `vi-command'; `emacs' is equivalent to `emacs-standard'. The + default value is `emacs'. The value of the `editing-mode' + variable also affects the default keymap. + + `mark-directories' + If set to `on', completed directory names have a slash + appended. The default is `on'. + + `mark-modified-lines' + This variable, when set to `on', causes Readline to display an + asterisk (`*') at the start of history lines which have been + modified. This variable is `off' by default. + + `input-meta' + If set to `on', Readline will enable eight-bit input (it will + not strip the eighth bit from the characters it reads), + regardless of what the terminal claims it can support. The + default value is `off'. The name `meta-flag' is a synonym + for this variable. + + `output-meta' + If set to `on', Readline will display characters with the + eighth bit set directly rather than as a meta-prefixed escape + sequence. The default is `off'. + + `print-completions-horizontally' + If set to `on', Readline will display completions with matches + sorted horizontally in alphabetical order, rather than down + the screen. The default is `off'. + + `show-all-if-ambiguous' + This alters the default behavior of the completion functions. + If set to `on', words which have more than one possible + completion cause the matches to be listed immediately instead + of ringing the bell. The default value is `off'. + + `visible-stats' + If set to `on', a character denoting a file's type is + appended to the filename when listing possible completions. + The default is `off'. + +Key Bindings + The syntax for controlling key bindings in the init file is + simple. First you have to know the name of the command that you + want to change. The following sections contain tables of the + command name, the default keybinding, if any, and a short + description of what the command does. + + Once you know the name of the command, simply place the name of + the key you wish to bind the command to, a colon, and then the + name of the command on a line in the init file. The name of the + key can be expressed in different ways, depending on which is most + comfortable for you. + + KEYNAME: FUNCTION-NAME or MACRO + KEYNAME is the name of a key spelled out in English. For + example: + Control-u: universal-argument + Meta-Rubout: backward-kill-word + Control-o: "> output" + + In the above example, <C-u> is bound to the function + `universal-argument', and <C-o> is bound to run the macro + expressed on the right hand side (that is, to insert the text + `> output' into the line). + + "KEYSEQ": FUNCTION-NAME or MACRO + KEYSEQ differs from KEYNAME above in that strings denoting an + entire key sequence can be specified, by placing the key + sequence in double quotes. Some GNU Emacs style key escapes + can be used, as in the following example, but the special + character names are not recognized. + + "\C-u": universal-argument + "\C-x\C-r": re-read-init-file + "\e[11~": "Function Key 1" + + In the above example, <C-u> is bound to the function + `universal-argument' (just as it was in the first example), + `<C-x> <C-r>' is bound to the function `re-read-init-file', + and `<ESC> <[> <1> <1> <~>' is bound to insert the text + `Function Key 1'. + + The following GNU Emacs style escape sequences are available when + specifying key sequences: + + `\C-' + control prefix + + `\M-' + meta prefix + + `\e' + an escape character + + `\\' + backslash + + `\"' + <"> + + `\'' + <'> + + In addition to the GNU Emacs style escape sequences, a second set + of backslash escapes is available: + + `\a' + alert (bell) + + `\b' + backspace + + `\d' + delete + + `\f' + form feed + + `\n' + newline + + `\r' + carriage return + + `\t' + horizontal tab + + `\v' + vertical tab + + `\NNN' + the character whose ASCII code is the octal value NNN (one to + three digits) + + `\xNNN' + the character whose ASCII code is the hexadecimal value NNN + (one to three digits) + + When entering the text of a macro, single or double quotes must be + used to indicate a macro definition. Unquoted text is assumed to + be a function name. In the macro body, the backslash escapes + described above are expanded. Backslash will quote any other + character in the macro text, including `"' and `''. For example, + the following binding will make `C-x \' insert a single `\' into + the line: + "\C-x\\": "\\" + + +File: gdb.info, Node: Conditional Init Constructs, Next: Sample Init File, Prev: Readline Init File Syntax, Up: Readline Init File + +Conditional Init Constructs +--------------------------- + + Readline implements a facility similar in spirit to the conditional +compilation features of the C preprocessor which allows key bindings +and variable settings to be performed as the result of tests. There +are four parser directives used. + +`$if' + The `$if' construct allows bindings to be made based on the + editing mode, the terminal being used, or the application using + Readline. The text of the test extends to the end of the line; no + characters are required to isolate it. + + `mode' + The `mode=' form of the `$if' directive is used to test + whether Readline is in `emacs' or `vi' mode. This may be + used in conjunction with the `set keymap' command, for + instance, to set bindings in the `emacs-standard' and + `emacs-ctlx' keymaps only if Readline is starting out in + `emacs' mode. + + `term' + The `term=' form may be used to include terminal-specific key + bindings, perhaps to bind the key sequences output by the + terminal's function keys. The word on the right side of the + `=' is tested against both the full name of the terminal and + the portion of the terminal name before the first `-'. This + allows `sun' to match both `sun' and `sun-cmd', for instance. + + `application' + The APPLICATION construct is used to include + application-specific settings. Each program using the + Readline library sets the APPLICATION NAME, and you can test + for it. This could be used to bind key sequences to + functions useful for a specific program. For instance, the + following command adds a key sequence that quotes the current + or previous word in Bash: + $if Bash + # Quote the current or previous word + "\C-xq": "\eb\"\ef\"" + $endif + +`$endif' + This command, as seen in the previous example, terminates an `$if' + command. + +`$else' + Commands in this branch of the `$if' directive are executed if the + test fails. + +`$include' + This directive takes a single filename as an argument and reads + commands and bindings from that file. + $include /etc/inputrc + + +File: gdb.info, Node: Sample Init File, Prev: Conditional Init Constructs, Up: Readline Init File + +Sample Init File +---------------- + + Here is an example of an inputrc file. This illustrates key +binding, variable assignment, and conditional syntax. + + + # This file controls the behaviour of line input editing for + # programs that use the Gnu Readline library. Existing programs + # include FTP, Bash, and Gdb. + # + # You can re-read the inputrc file with C-x C-r. + # Lines beginning with '#' are comments. + # + # First, include any systemwide bindings and variable assignments from + # /etc/Inputrc + $include /etc/Inputrc + + # + # Set various bindings for emacs mode. + + set editing-mode emacs + + $if mode=emacs + + Meta-Control-h: backward-kill-word Text after the function name is ignored + + # + # Arrow keys in keypad mode + # + #"\M-OD": backward-char + #"\M-OC": forward-char + #"\M-OA": previous-history + #"\M-OB": next-history + # + # Arrow keys in ANSI mode + # + "\M-[D": backward-char + "\M-[C": forward-char + "\M-[A": previous-history + "\M-[B": next-history + # + # Arrow keys in 8 bit keypad mode + # + #"\M-\C-OD": backward-char + #"\M-\C-OC": forward-char + #"\M-\C-OA": previous-history + #"\M-\C-OB": next-history + # + # Arrow keys in 8 bit ANSI mode + # + #"\M-\C-[D": backward-char + #"\M-\C-[C": forward-char + #"\M-\C-[A": previous-history + #"\M-\C-[B": next-history + + C-q: quoted-insert + + $endif + + # An old-style binding. This happens to be the default. + TAB: complete + + # Macros that are convenient for shell interaction + $if Bash + # edit the path + "\C-xp": "PATH=${PATH}\e\C-e\C-a\ef\C-f" + # prepare to type a quoted word -- insert open and close double quotes + # and move to just after the open quote + "\C-x\"": "\"\"\C-b" + # insert a backslash (testing backslash escapes in sequences and macros) + "\C-x\\": "\\" + # Quote the current or previous word + "\C-xq": "\eb\"\ef\"" + # Add a binding to refresh the line, which is unbound + "\C-xr": redraw-current-line + # Edit variable on current line. + "\M-\C-v": "\C-a\C-k$\C-y\M-\C-e\C-a\C-y=" + $endif + + # use a visible bell if one is available + set bell-style visible + + # don't strip characters to 7 bits when reading + set input-meta on + + # allow iso-latin1 characters to be inserted rather than converted to + # prefix-meta sequences + set convert-meta off + + # display characters with the eighth bit set directly rather than + # as meta-prefixed characters + set output-meta on + + # if there are more than 150 possible completions for a word, ask the + # user if he wants to see all of them + set completion-query-items 150 + + # For FTP + $if Ftp + "\C-xg": "get \M-?" + "\C-xt": "put \M-?" + "\M-.": yank-last-arg + $endif + + +File: gdb.info, Node: Bindable Readline Commands, Next: Readline vi Mode, Prev: Readline Init File, Up: Command Line Editing + +Bindable Readline Commands +========================== + +* Menu: + +* Commands For Moving:: Moving about the line. +* Commands For History:: Getting at previous lines. +* Commands For Text:: Commands for changing text. +* Commands For Killing:: Commands for killing and yanking. +* Numeric Arguments:: Specifying numeric arguments, repeat counts. +* Commands For Completion:: Getting Readline to do the typing for you. +* Keyboard Macros:: Saving and re-executing typed characters +* Miscellaneous Commands:: Other miscellaneous commands. + + This section describes Readline commands that may be bound to key +sequences. + + +File: gdb.info, Node: Commands For Moving, Next: Commands For History, Up: Bindable Readline Commands + +Commands For Moving +------------------- + +`beginning-of-line (C-a)' + Move to the start of the current line. + +`end-of-line (C-e)' + Move to the end of the line. + +`forward-char (C-f)' + Move forward a character. + +`backward-char (C-b)' + Move back a character. + +`forward-word (M-f)' + Move forward to the end of the next word. Words are composed of + letters and digits. + +`backward-word (M-b)' + Move back to the start of this, or the previous, word. Words are + composed of letters and digits. + +`clear-screen (C-l)' + Clear the screen and redraw the current line, leaving the current + line at the top of the screen. + +`redraw-current-line ()' + Refresh the current line. By default, this is unbound. + + +File: gdb.info, Node: Commands For History, Next: Commands For Text, Prev: Commands For Moving, Up: Bindable Readline Commands + +Commands For Manipulating The History +------------------------------------- + +`accept-line (Newline, Return)' + Accept the line regardless of where the cursor is. If this line is + non-empty, add it to the history list. If this line was a history + line, then restore the history line to its original state. + +`previous-history (C-p)' + Move `up' through the history list. + +`next-history (C-n)' + Move `down' through the history list. + +`beginning-of-history (M-<)' + Move to the first line in the history. + +`end-of-history (M->)' + Move to the end of the input history, i.e., the line currently + being entered. + +`reverse-search-history (C-r)' + Search backward starting at the current line and moving `up' + through the history as necessary. This is an incremental search. + +`forward-search-history (C-s)' + Search forward starting at the current line and moving `down' + through the the history as necessary. This is an incremental + search. + +`non-incremental-reverse-search-history (M-p)' + Search backward starting at the current line and moving `up' + through the history as necessary using a non-incremental search + for a string supplied by the user. + +`non-incremental-forward-search-history (M-n)' + Search forward starting at the current line and moving `down' + through the the history as necessary using a non-incremental search + for a string supplied by the user. + +`history-search-forward ()' + Search forward through the history for the string of characters + between the start of the current line and the current cursor + position (the POINT). This is a non-incremental search. By + default, this command is unbound. + +`history-search-backward ()' + Search backward through the history for the string of characters + between the start of the current line and the point. This is a + non-incremental search. By default, this command is unbound. + +`yank-nth-arg (M-C-y)' + Insert the first argument to the previous command (usually the + second word on the previous line). With an argument N, insert the + Nth word from the previous command (the words in the previous + command begin with word 0). A negative argument inserts the Nth + word from the end of the previous command. + +`yank-last-arg (M-., M-_)' + Insert last argument to the previous command (the last word of the + previous history entry). With an argument, behave exactly like + `yank-nth-arg'. Successive calls to `yank-last-arg' move back + through the history list, inserting the last argument of each line + in turn. + + +File: gdb.info, Node: Commands For Text, Next: Commands For Killing, Prev: Commands For History, Up: Bindable Readline Commands + +Commands For Changing Text +-------------------------- + +`delete-char (C-d)' + Delete the character under the cursor. If the cursor is at the + beginning of the line, there are no characters in the line, and + the last character typed was not bound to `delete-char', then + return `EOF'. + +`backward-delete-char (Rubout)' + Delete the character behind the cursor. A numeric argument means + to kill the characters instead of deleting them. + +`quoted-insert (C-q, C-v)' + Add the next character typed to the line verbatim. This is how to + insert key sequences like <C-q>, for example. + +`tab-insert (M-TAB)' + Insert a tab character. + +`self-insert (a, b, A, 1, !, ...)' + Insert yourself. + +`transpose-chars (C-t)' + Drag the character before the cursor forward over the character at + the cursor, moving the cursor forward as well. If the insertion + point is at the end of the line, then this transposes the last two + characters of the line. Negative arguments don't work. + +`transpose-words (M-t)' + Drag the word behind the cursor past the word in front of the + cursor moving the cursor over that word as well. + +`upcase-word (M-u)' + Uppercase the current (or following) word. With a negative + argument, uppercase the previous word, but do not move the cursor. + +`downcase-word (M-l)' + Lowercase the current (or following) word. With a negative + argument, lowercase the previous word, but do not move the cursor. + +`capitalize-word (M-c)' + Capitalize the current (or following) word. With a negative + argument, capitalize the previous word, but do not move the cursor. + + +File: gdb.info, Node: Commands For Killing, Next: Numeric Arguments, Prev: Commands For Text, Up: Bindable Readline Commands + +Killing And Yanking +------------------- + +`kill-line (C-k)' + Kill the text from the current cursor position to the end of the + line. + +`backward-kill-line (C-x Rubout)' + Kill backward to the beginning of the line. + +`unix-line-discard (C-u)' + Kill backward from the cursor to the beginning of the current line. + The killed text is saved on the kill-ring. + +`kill-whole-line ()' + Kill all characters on the current line, no matter where the + cursor is. By default, this is unbound. + +`kill-word (M-d)' + Kill from the cursor to the end of the current word, or if between + words, to the end of the next word. Word boundaries are the same + as `forward-word'. + +`backward-kill-word (M-DEL)' + Kill the word behind the cursor. Word boundaries are the same as + `backward-word'. + +`unix-word-rubout (C-w)' + Kill the word behind the cursor, using white space as a word + boundary. The killed text is saved on the kill-ring. + +`delete-horizontal-space ()' + Delete all spaces and tabs around point. By default, this is + unbound. + +`kill-region ()' + Kill the text between the point and the *mark* (saved cursor + position). This text is referred to as the REGION. By default, + this command is unbound. + +`copy-region-as-kill ()' + Copy the text in the region to the kill buffer, so it can be yanked + right away. By default, this command is unbound. + +`copy-backward-word ()' + Copy the word before point to the kill buffer. The word + boundaries are the same as `backward-word'. By default, this + command is unbound. + +`copy-forward-word ()' + Copy the word following point to the kill buffer. The word + boundaries are the same as `forward-word'. By default, this + command is unbound. + +`yank (C-y)' + Yank the top of the kill ring into the buffer at the current + cursor position. + +`yank-pop (M-y)' + Rotate the kill-ring, and yank the new top. You can only do this + if the prior command is yank or yank-pop. + + +File: gdb.info, Node: Numeric Arguments, Next: Commands For Completion, Prev: Commands For Killing, Up: Bindable Readline Commands + +Specifying Numeric Arguments +---------------------------- + +`digit-argument (M-0, M-1, ... M--)' + Add this digit to the argument already accumulating, or start a new + argument. <M-> starts a negative argument. + +`universal-argument ()' + This is another way to specify an argument. If this command is + followed by one or more digits, optionally with a leading minus + sign, those digits define the argument. If the command is + followed by digits, executing `universal-argument' again ends the + numeric argument, but is otherwise ignored. As a special case, if + this command is immediately followed by a character that is + neither a digit or minus sign, the argument count for the next + command is multiplied by four. The argument count is initially + one, so executing this function the first time makes the argument + count four, a second time makes the argument count sixteen, and so + on. By default, this is not bound to a key. + |