<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html><head><meta http-equiv="Content-Type" content="text/html;charset=iso-8859-1"> <title>Apache Portable Runtime: apr_shm.h Source File</title> <link href="doxygen.css" rel="stylesheet" type="text/css"> </head><body> <!-- Generated by Doxygen 1.3.9.1 --> <div class="qindex"><a class="qindex" href="index.html">Main Page</a> | <a class="qindex" href="modules.html">Modules</a> | <a class="qindex" href="annotated.html">Data Structures</a> | <a class="qindex" href="files.html">File List</a> | <a class="qindex" href="functions.html">Data Fields</a> | <a class="qindex" href="globals.html">Globals</a> | <a class="qindex" href="pages.html">Related Pages</a></div> <div class="nav"> <a class="el" href="dir_000000.html">home</a> / <a class="el" href="dir_000001.html">oden</a> / <a class="el" href="dir_000002.html">RPM</a> / <a class="el" href="dir_000003.html">BUILD</a> / <a class="el" href="dir_000004.html">apr-1.1.1</a> / <a class="el" href="dir_000005.html">include</a></div> <h1>apr_shm.h</h1><a href="apr__shm_8h.html">Go to the documentation of this file.</a><div class="fragment"><pre class="fragment">00001 <span class="comment">/* Copyright 2000-2004 The Apache Software Foundation</span> 00002 <span class="comment"> *</span> 00003 <span class="comment"> * Licensed under the Apache License, Version 2.0 (the "License");</span> 00004 <span class="comment"> * you may not use this file except in compliance with the License.</span> 00005 <span class="comment"> * You may obtain a copy of the License at</span> 00006 <span class="comment"> *</span> 00007 <span class="comment"> * http://www.apache.org/licenses/LICENSE-2.0</span> 00008 <span class="comment"> *</span> 00009 <span class="comment"> * Unless required by applicable law or agreed to in writing, software</span> 00010 <span class="comment"> * distributed under the License is distributed on an "AS IS" BASIS,</span> 00011 <span class="comment"> * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.</span> 00012 <span class="comment"> * See the License for the specific language governing permissions and</span> 00013 <span class="comment"> * limitations under the License.</span> 00014 <span class="comment"> */</span> 00015 00016 <span class="preprocessor">#ifndef APR_SHM_H</span> 00017 <span class="preprocessor"></span><span class="preprocessor">#define APR_SHM_H</span> 00018 <span class="preprocessor"></span><span class="comment"></span> 00019 <span class="comment">/**</span> 00020 <span class="comment"> * @file apr_shm.h</span> 00021 <span class="comment"> * @brief APR Shared Memory Routines</span> 00022 <span class="comment"> */</span> 00023 00024 <span class="preprocessor">#include "<a class="code" href="apr_8h.html">apr.h</a>"</span> 00025 <span class="preprocessor">#include "<a class="code" href="apr__pools_8h.html">apr_pools.h</a>"</span> 00026 <span class="preprocessor">#include "<a class="code" href="apr__errno_8h.html">apr_errno.h</a>"</span> 00027 00028 <span class="preprocessor">#ifdef __cplusplus</span> 00029 <span class="preprocessor"></span><span class="keyword">extern</span> <span class="stringliteral">"C"</span> { 00030 <span class="preprocessor">#endif </span><span class="comment">/* __cplusplus */</span> 00031 <span class="comment"></span> 00032 <span class="comment">/**</span> 00033 <span class="comment"> * @defgroup apr_shm Shared Memory Routines</span> 00034 <span class="comment"> * @ingroup APR </span> 00035 <span class="comment"> * @{</span> 00036 <span class="comment"> */</span> 00037 <span class="comment"></span> 00038 <span class="comment">/**</span> 00039 <span class="comment"> * Private, platform-specific data struture representing a shared memory</span> 00040 <span class="comment"> * segment.</span> 00041 <span class="comment"> */</span> <a name="l00042"></a><a class="code" href="group__apr__shm.html#ga0">00042</a> <span class="keyword">typedef</span> <span class="keyword">struct </span><a class="code" href="group__apr__shm.html#ga0">apr_shm_t</a> <a class="code" href="group__apr__shm.html#ga0">apr_shm_t</a>; 00043 <span class="comment"></span> 00044 <span class="comment">/**</span> 00045 <span class="comment"> * Create and make accessable a shared memory segment.</span> 00046 <span class="comment"> * @param m The shared memory structure to create.</span> 00047 <span class="comment"> * @param reqsize The desired size of the segment.</span> 00048 <span class="comment"> * @param filename The file to use for shared memory on platforms that</span> 00049 <span class="comment"> * require it.</span> 00050 <span class="comment"> * @param pool the pool from which to allocate the shared memory</span> 00051 <span class="comment"> * structure.</span> 00052 <span class="comment"> * @remark A note about Anonymous vs. Named shared memory segments:</span> 00053 <span class="comment"> * Not all plaforms support anonymous shared memory segments, but in</span> 00054 <span class="comment"> * some cases it is prefered over other types of shared memory</span> 00055 <span class="comment"> * implementations. Passing a NULL 'file' parameter to this function</span> 00056 <span class="comment"> * will cause the subsystem to use anonymous shared memory segments.</span> 00057 <span class="comment"> * If such a system is not available, APR_ENOTIMPL is returned.</span> 00058 <span class="comment"> * @remark A note about allocation sizes:</span> 00059 <span class="comment"> * On some platforms it is necessary to store some metainformation</span> 00060 <span class="comment"> * about the segment within the actual segment. In order to supply</span> 00061 <span class="comment"> * the caller with the requested size it may be necessary for the</span> 00062 <span class="comment"> * implementation to request a slightly greater segment length</span> 00063 <span class="comment"> * from the subsystem. In all cases, the apr_shm_baseaddr_get()</span> 00064 <span class="comment"> * function will return the first usable byte of memory.</span> 00065 <span class="comment"> * </span> 00066 <span class="comment"> */</span> 00067 <a class="code" href="group__apr__platform.html#ga123">APR_DECLARE</a>(apr_status_t) apr_shm_create(apr_shm_t **m, 00068 apr_size_t reqsize, 00069 const <span class="keywordtype">char</span> *filename, 00070 apr_pool_t *pool); 00071 <span class="comment"></span> 00072 <span class="comment">/**</span> 00073 <span class="comment"> * Remove shared memory segment associated with a filename.</span> 00074 <span class="comment"> * @param filename The filename associated with shared-memory segment which</span> 00075 <span class="comment"> * needs to be removed</span> 00076 <span class="comment"> * @param pool The pool used for file operations</span> 00077 <span class="comment"> * @remark This function is only supported on platforms which support</span> 00078 <span class="comment"> * name-based shared memory segments, and will return APR_ENOTIMPL on</span> 00079 <span class="comment"> * platforms without such support.</span> 00080 <span class="comment"> */</span> 00081 APR_DECLARE(apr_status_t) apr_shm_remove(const <span class="keywordtype">char</span> *filename, 00082 apr_pool_t *pool); 00083 <span class="comment"></span> 00084 <span class="comment">/**</span> 00085 <span class="comment"> * Destroy a shared memory segment and associated memory.</span> 00086 <span class="comment"> * @param m The shared memory segment structure to destroy.</span> 00087 <span class="comment"> */</span> 00088 APR_DECLARE(apr_status_t) apr_shm_destroy(apr_shm_t *m); 00089 <span class="comment"></span> 00090 <span class="comment">/**</span> 00091 <span class="comment"> * Attach to a shared memory segment that was created</span> 00092 <span class="comment"> * by another process.</span> 00093 <span class="comment"> * @param m The shared memory structure to create.</span> 00094 <span class="comment"> * @param filename The file used to create the original segment.</span> 00095 <span class="comment"> * (This MUST match the original filename.)</span> 00096 <span class="comment"> * @param pool the pool from which to allocate the shared memory</span> 00097 <span class="comment"> * structure for this process.</span> 00098 <span class="comment"> */</span> 00099 APR_DECLARE(apr_status_t) apr_shm_attach(apr_shm_t **m, 00100 const <span class="keywordtype">char</span> *filename, 00101 apr_pool_t *pool); 00102 <span class="comment"></span> 00103 <span class="comment">/**</span> 00104 <span class="comment"> * Detach from a shared memory segment without destroying it.</span> 00105 <span class="comment"> * @param m The shared memory structure representing the segment</span> 00106 <span class="comment"> * to detach from.</span> 00107 <span class="comment"> */</span> 00108 APR_DECLARE(apr_status_t) apr_shm_detach(apr_shm_t *m); 00109 <span class="comment"></span> 00110 <span class="comment">/**</span> 00111 <span class="comment"> * Retrieve the base address of the shared memory segment.</span> 00112 <span class="comment"> * NOTE: This address is only usable within the callers address</span> 00113 <span class="comment"> * space, since this API does not guarantee that other attaching</span> 00114 <span class="comment"> * processes will maintain the same address mapping.</span> 00115 <span class="comment"> * @param m The shared memory segment from which to retrieve</span> 00116 <span class="comment"> * the base address.</span> 00117 <span class="comment"> * @return address, aligned by APR_ALIGN_DEFAULT.</span> 00118 <span class="comment"> */</span> 00119 APR_DECLARE(<span class="keywordtype">void</span> *) apr_shm_baseaddr_get(const apr_shm_t *m); 00120 <span class="comment"></span> 00121 <span class="comment">/**</span> 00122 <span class="comment"> * Retrieve the length of a shared memory segment in bytes.</span> 00123 <span class="comment"> * @param m The shared memory segment from which to retrieve</span> 00124 <span class="comment"> * the segment length.</span> 00125 <span class="comment"> */</span> 00126 APR_DECLARE(apr_size_t) apr_shm_size_get(const apr_shm_t *m); 00127 <span class="comment"></span> 00128 <span class="comment">/**</span> 00129 <span class="comment"> * Get the pool used by this shared memory segment.</span> 00130 <span class="comment"> */</span> 00131 APR_POOL_DECLARE_ACCESSOR(shm); 00132 <span class="comment"></span> 00133 <span class="comment">/** @} */</span> 00134 00135 #ifdef __cplusplus 00136 } 00137 #endif 00138 00139 #endif <span class="comment">/* APR_SHM_T */</span> </pre></div><hr size="1"><address style="align: right;"><small>Generated on Sun Mar 20 19:52:26 2005 for Apache Portable Runtime by <a href="http://www.doxygen.org/index.html"> <img src="doxygen.png" alt="doxygen" align="middle" border="0"></a> 1.3.9.1 </small></address> </body> </html>