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| author | Lorry Tar Creator <lorry-tar-importer@baserock.org> | 2015-02-17 17:25:57 +0000 |
|---|---|---|
| committer | <> | 2015-03-17 16:26:24 +0000 |
| commit | 780b92ada9afcf1d58085a83a0b9e6bc982203d1 (patch) | |
| tree | 598f8b9fa431b228d29897e798de4ac0c1d3d970 /docs/programmer_reference/ext.html | |
| parent | 7a2660ba9cc2dc03a69ddfcfd95369395cc87444 (diff) | |
| download | berkeleydb-master.tar.gz | |
Diffstat (limited to 'docs/programmer_reference/ext.html')
| -rw-r--r-- | docs/programmer_reference/ext.html | 152 |
1 files changed, 97 insertions, 55 deletions
diff --git a/docs/programmer_reference/ext.html b/docs/programmer_reference/ext.html index 31d38bd9..c73bea92 100644 --- a/docs/programmer_reference/ext.html +++ b/docs/programmer_reference/ext.html @@ -14,13 +14,11 @@ <body> <div xmlns="" class="navheader"> <div class="libver"> - <p>Library Version 11.2.5.3</p> + <p>Library Version 12.1.6.1</p> </div> <table width="100%" summary="Navigation header"> <tr> - <th colspan="3" align="center">Chapter 22. - Berkeley DB Extensions - </th> + <th colspan="3" align="center">Chapter 22. Berkeley DB Extensions </th> </tr> <tr> <td width="20%" align="left"><a accesskey="p" href="tcl_faq.html">Prev</a> </td> @@ -34,9 +32,7 @@ <div class="titlepage"> <div> <div> - <h2 class="title"><a id="ext"></a>Chapter 22. - Berkeley DB Extensions - </h2> + <h2 class="title"><a id="ext"></a>Chapter 22. Berkeley DB Extensions </h2> </div> </div> </div> @@ -70,64 +66,110 @@ </div> </div> </div> - <p>A mod_db4 Apache module is included in the Berkeley DB distribution, providing -a safe framework for running Berkeley DB applications in an Apache 1.3 -environment. Apache natively provides no interface for communication -between threads or processes, so the mod_db4 module exists to provide -this communication.</p> - <p>In general, it is dangerous to run Berkeley DB in a multiprocess system -without some facility to coordinate database recovery between processes -sharing the database environment after application or system failure. -Failure to run recovery after failure can include process hangs and an -inability to access the database environment. The mod_db4 Apache module -oversees the proper management of Berkeley DB database environment resources. -Developers building applications using Berkeley DB as the storage manager -within an Apache module should employ this technique for proper resource -management.</p> - <p>Specifically, mod_db4 provides the following facilities:</p> + <p> + A mod_db4 Apache module is included in the Berkeley DB + distribution, providing a safe framework for running Berkeley + DB applications in an Apache 1.3 environment. Apache natively + provides no interface for communication between threads or + processes, so the mod_db4 module exists to provide this + communication. + </p> + <p> + In general, it is dangerous to run Berkeley DB in a + multiprocess system without some facility to coordinate + database recovery between processes sharing the database + environment after application or system failure. Failure to + run recovery after failure can include process hangs and an + inability to access the database environment. The mod_db4 + Apache module oversees the proper management of Berkeley DB + database environment resources. Developers building + applications using Berkeley DB as the storage manager within + an Apache module should employ this technique for proper + resource management. + </p> + <p> + Specifically, mod_db4 provides the following + facilities: + </p> <div class="orderedlist"> <ol type="1"> - <li>New constructors for <a href="../api_reference/C/env.html" class="olink">DB_ENV</a> and <a href="../api_reference/C/db.html" class="olink">DB</a> handles, which install -replacement open/close methods.</li> - <li>Transparent caching of open <a href="../api_reference/C/env.html" class="olink">DB_ENV</a> and <a href="../api_reference/C/db.html" class="olink">DB</a> handles.</li> - <li>Reference counting on all structures, allowing the module to detect the -initial opening of any managed database and automatically perform recovery.</li> - <li>Automatic detection of unexpected failures (segfaults, or a module -actually calling exit() and avoiding shut down phases), and automatic -termination of all child processes with open database resources to -attempt consistency.</li> + <li> + New constructors for <a href="../api_reference/C/env.html" class="olink">DB_ENV</a> and <a href="../api_reference/C/db.html" class="olink">DB</a> handles, which + install replacement open/close methods. + </li> + <li> + Transparent caching of open <a href="../api_reference/C/env.html" class="olink">DB_ENV</a> and <a href="../api_reference/C/db.html" class="olink">DB</a> + handles. + </li> + <li> + Reference counting on all structures, allowing the + module to detect the initial opening of any managed + database and automatically perform recovery. + </li> + <li> + Automatic detection of unexpected failures + (segfaults, or a module actually calling exit() and + avoiding shut down phases), and automatic termination of + all child processes with open database resources to + attempt consistency. + </li> </ol> </div> - <p>mod_db4 is designed to be used as an alternative interface to Berkeley DB. To -have another Apache module (for example, mod_foo) use mod_db4, do not -link mod_foo against the Berkeley DB library. In your mod_foo makefile, you -should:</p> + <p> + mod_db4 is designed to be used as an alternative interface + to Berkeley DB. To have another Apache module (for example, + mod_foo) use mod_db4, do not link mod_foo against the Berkeley + DB library. In your mod_foo makefile, you should: + </p> <pre class="programlisting">#include "mod_db4_export.h"</pre> - <p>and add your Apache include directory to your CPPFLAGS.</p> - <p>In mod_foo, to create a mod_db4 managed <a href="../api_reference/C/env.html" class="olink">DB_ENV</a> handle, use the -following:</p> + <p> + and add your Apache include directory to your + CPPFLAGS. + </p> + <p> + In mod_foo, to create a mod_db4 managed <a href="../api_reference/C/env.html" class="olink">DB_ENV</a> handle, use + the following: + </p> <pre class="programlisting">int mod_db4_db_env_create(DB_ENV **dbenvp, u_int32_t flags);</pre> - <p>which takes identical arguments to <a href="../api_reference/C/envcreate.html" class="olink">db_env_create()</a>.</p> - <p>To create a mod_db4 managed <a href="../api_reference/C/db.html" class="olink">DB</a> handle, use the following:</p> + <p> + which takes identical arguments to <a href="../api_reference/C/envcreate.html" class="olink">db_env_create()</a>. + </p> + <p> + To create a mod_db4 managed <a href="../api_reference/C/db.html" class="olink">DB</a> handle, use the + following: + </p> <pre class="programlisting">int mod_db4_db_create(DB **dbp, DB_ENV *dbenv, u_int32_t flags);</pre> - <p>which takes identical arguments to <a href="../api_reference/C/dbcreate.html" class="olink">db_create()</a>.</p> - <p>Otherwise the API is completely consistent with the standard Berkeley DB -API.</p> - <p>The mod_db4 module requires the Berkeley DB library be compiled with C++ -extensions and the MM library. (The MM library provides an abstraction -layer which allows related processes to share data easily. On systems -where shared memory or other inter-process communication mechanisms are -not available, the MM library emulates them using temporary files. MM -is used in several operating systems to provide shared memory pools to -Apache modules.)</p> - <p>To build this apache module, perform the following steps:</p> + <p> + which takes identical arguments to <a href="../api_reference/C/dbcreate.html" class="olink">db_create()</a>. + </p> + <p> + Otherwise the API is completely consistent with the standard + Berkeley DB API. + </p> + <p> + The mod_db4 module requires the Berkeley DB library be + compiled with C++ extensions and the MM library. (The MM + library provides an abstraction layer which allows related + processes to share data easily. On systems where shared memory + or other inter-process communication mechanisms are not + available, the MM library emulates them using temporary files. + MM is used in several operating systems to provide shared + memory pools to Apache modules.) + </p> + <p> + To build this apache module, perform the following + steps: + </p> <pre class="programlisting">% ./configure --with-apxs=[path to the apxs utility] \ - --with-db4=[Berkeley DB library installation directory] \ - --with-mm=[libmm installation directory] + --with-db4=[Berkeley DB library installation directory] \ + --with-mm=[libmm installation directory] % make % make install</pre> - <p>Post-installation, modules can use this extension via the functions -documented in $APACHE_INCLUDEDIR/mod_db4_export.h.</p> + <p> + Post-installation, modules can use this extension via the + functions documented in + $APACHE_INCLUDEDIR/mod_db4_export.h. + </p> </div> </div> <div class="navfooter"> |