<!-- This comment will put IE 6, 7 and 8 in quirks mode --> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/xhtml;charset=UTF-8"/> <title>Apache Portable Runtime: apr_shm.h Source File</title> <link href="tabs.css" rel="stylesheet" type="text/css"/> <link href="search/search.css" rel="stylesheet" type="text/css"/> <script type="text/javaScript" src="search/search.js"></script> <link href="doxygen.css" rel="stylesheet" type="text/css"/> </head> <body onload='searchBox.OnSelectItem(0);'> <!-- Generated by Doxygen 1.6.3 --> <script type="text/javascript"><!-- var searchBox = new SearchBox("searchBox", "search",false,'Search'); --></script> <div class="navigation" id="top"> <div class="tabs"> <ul> <li><a href="index.html"><span>Main Page</span></a></li> <li><a href="pages.html"><span>Related Pages</span></a></li> <li><a href="modules.html"><span>Modules</span></a></li> <li><a href="annotated.html"><span>Data Structures</span></a></li> <li class="current"><a href="files.html"><span>Files</span></a></li> <li> <div id="MSearchBox" class="MSearchBoxInactive"> <img id="MSearchSelect" src="search/search.png" onmouseover="return searchBox.OnSearchSelectShow()" onmouseout="return searchBox.OnSearchSelectHide()" alt=""/> <input type="text" id="MSearchField" value="Search" accesskey="S" onfocus="searchBox.OnSearchFieldFocus(true)" onblur="searchBox.OnSearchFieldFocus(false)" onkeyup="searchBox.OnSearchFieldChange(event)"/> <a id="MSearchClose" href="javascript:searchBox.CloseResultsWindow()"><img id="MSearchCloseImg" border="0" src="search/close.png" alt=""/></a> </div> </li> </ul> </div> <div class="tabs"> <ul> <li><a href="files.html"><span>File List</span></a></li> <li><a href="globals.html"><span>Globals</span></a></li> </ul> </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"><a name="l00001"></a>00001 <span class="comment">/* Licensed to the Apache Software Foundation (ASF) under one or more</span> <a name="l00002"></a>00002 <span class="comment"> * contributor license agreements. See the NOTICE file distributed with</span> <a name="l00003"></a>00003 <span class="comment"> * this work for additional information regarding copyright ownership.</span> <a name="l00004"></a>00004 <span class="comment"> * The ASF licenses this file to You under the Apache License, Version 2.0</span> <a name="l00005"></a>00005 <span class="comment"> * (the "License"); you may not use this file except in compliance with</span> <a name="l00006"></a>00006 <span class="comment"> * the License. You may obtain a copy of the License at</span> <a name="l00007"></a>00007 <span class="comment"> *</span> <a name="l00008"></a>00008 <span class="comment"> * http://www.apache.org/licenses/LICENSE-2.0</span> <a name="l00009"></a>00009 <span class="comment"> *</span> <a name="l00010"></a>00010 <span class="comment"> * Unless required by applicable law or agreed to in writing, software</span> <a name="l00011"></a>00011 <span class="comment"> * distributed under the License is distributed on an "AS IS" BASIS,</span> <a name="l00012"></a>00012 <span class="comment"> * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.</span> <a name="l00013"></a>00013 <span class="comment"> * See the License for the specific language governing permissions and</span> <a name="l00014"></a>00014 <span class="comment"> * limitations under the License.</span> <a name="l00015"></a>00015 <span class="comment"> */</span> <a name="l00016"></a>00016 <a name="l00017"></a>00017 <span class="preprocessor">#ifndef APR_SHM_H</span> <a name="l00018"></a>00018 <span class="preprocessor"></span><span class="preprocessor">#define APR_SHM_H</span> <a name="l00019"></a>00019 <span class="preprocessor"></span><span class="comment"></span> <a name="l00020"></a>00020 <span class="comment">/**</span> <a name="l00021"></a>00021 <span class="comment"> * @file apr_shm.h</span> <a name="l00022"></a>00022 <span class="comment"> * @brief APR Shared Memory Routines</span> <a name="l00023"></a>00023 <span class="comment"> */</span> <a name="l00024"></a>00024 <a name="l00025"></a>00025 <span class="preprocessor">#include "<a class="code" href="apr_8h.html" title="APR Platform Definitions.">apr.h</a>"</span> <a name="l00026"></a>00026 <span class="preprocessor">#include "<a class="code" href="apr__pools_8h.html" title="APR memory allocation.">apr_pools.h</a>"</span> <a name="l00027"></a>00027 <span class="preprocessor">#include "<a class="code" href="apr__errno_8h.html" title="APR Error Codes.">apr_errno.h</a>"</span> <a name="l00028"></a>00028 <a name="l00029"></a>00029 <span class="preprocessor">#ifdef __cplusplus</span> <a name="l00030"></a>00030 <span class="preprocessor"></span><span class="keyword">extern</span> <span class="stringliteral">"C"</span> { <a name="l00031"></a>00031 <span class="preprocessor">#endif </span><span class="comment">/* __cplusplus */</span> <a name="l00032"></a>00032 <span class="comment"></span> <a name="l00033"></a>00033 <span class="comment">/**</span> <a name="l00034"></a>00034 <span class="comment"> * @defgroup apr_shm Shared Memory Routines</span> <a name="l00035"></a>00035 <span class="comment"> * @ingroup APR </span> <a name="l00036"></a>00036 <span class="comment"> * @{</span> <a name="l00037"></a>00037 <span class="comment"> */</span> <a name="l00038"></a>00038 <span class="comment"></span> <a name="l00039"></a>00039 <span class="comment">/**</span> <a name="l00040"></a>00040 <span class="comment"> * Private, platform-specific data struture representing a shared memory</span> <a name="l00041"></a>00041 <span class="comment"> * segment.</span> <a name="l00042"></a>00042 <span class="comment"> */</span> <a name="l00043"></a><a class="code" href="group__apr__shm.html#ga79e8c16bdeaf7ade4ef0f935249e7c2f">00043</a> <span class="keyword">typedef</span> <span class="keyword">struct </span><a class="code" href="group__apr__shm.html#ga79e8c16bdeaf7ade4ef0f935249e7c2f">apr_shm_t</a> <a class="code" href="group__apr__shm.html#ga79e8c16bdeaf7ade4ef0f935249e7c2f">apr_shm_t</a>; <a name="l00044"></a>00044 <span class="comment"></span> <a name="l00045"></a>00045 <span class="comment">/**</span> <a name="l00046"></a>00046 <span class="comment"> * Create and make accessable a shared memory segment.</span> <a name="l00047"></a>00047 <span class="comment"> * @param m The shared memory structure to create.</span> <a name="l00048"></a>00048 <span class="comment"> * @param reqsize The desired size of the segment.</span> <a name="l00049"></a>00049 <span class="comment"> * @param filename The file to use for shared memory on platforms that</span> <a name="l00050"></a>00050 <span class="comment"> * require it.</span> <a name="l00051"></a>00051 <span class="comment"> * @param pool the pool from which to allocate the shared memory</span> <a name="l00052"></a>00052 <span class="comment"> * structure.</span> <a name="l00053"></a>00053 <span class="comment"> * @remark A note about Anonymous vs. Named shared memory segments:</span> <a name="l00054"></a>00054 <span class="comment"> * Not all plaforms support anonymous shared memory segments, but in</span> <a name="l00055"></a>00055 <span class="comment"> * some cases it is prefered over other types of shared memory</span> <a name="l00056"></a>00056 <span class="comment"> * implementations. Passing a NULL 'file' parameter to this function</span> <a name="l00057"></a>00057 <span class="comment"> * will cause the subsystem to use anonymous shared memory segments.</span> <a name="l00058"></a>00058 <span class="comment"> * If such a system is not available, APR_ENOTIMPL is returned.</span> <a name="l00059"></a>00059 <span class="comment"> * @remark A note about allocation sizes:</span> <a name="l00060"></a>00060 <span class="comment"> * On some platforms it is necessary to store some metainformation</span> <a name="l00061"></a>00061 <span class="comment"> * about the segment within the actual segment. In order to supply</span> <a name="l00062"></a>00062 <span class="comment"> * the caller with the requested size it may be necessary for the</span> <a name="l00063"></a>00063 <span class="comment"> * implementation to request a slightly greater segment length</span> <a name="l00064"></a>00064 <span class="comment"> * from the subsystem. In all cases, the apr_shm_baseaddr_get()</span> <a name="l00065"></a>00065 <span class="comment"> * function will return the first usable byte of memory.</span> <a name="l00066"></a>00066 <span class="comment"> * </span> <a name="l00067"></a>00067 <span class="comment"> */</span> <a name="l00068"></a>00068 <a class="code" href="group__apr__platform.html#gad7b91b811a172bfa802603c2fb688f98">APR_DECLARE</a>(<a class="code" href="group__apr__errno.html#gaf76ee4543247e9fb3f3546203e590a6c">apr_status_t</a>) <a class="code" href="group__apr__shm.html#gac370c4943c22505ce2b0d57c51805480">apr_shm_create</a>(<a class="code" href="group__apr__shm.html#ga79e8c16bdeaf7ade4ef0f935249e7c2f">apr_shm_t</a> **m, <a name="l00069"></a>00069 apr_size_t reqsize, <a name="l00070"></a>00070 const <span class="keywordtype">char</span> *filename, <a name="l00071"></a>00071 <a class="code" href="group__apr__pools.html#gaf137f28edcf9a086cd6bc36c20d7cdfb">apr_pool_t</a> *pool); <a name="l00072"></a>00072 <span class="comment"></span> <a name="l00073"></a>00073 <span class="comment">/**</span> <a name="l00074"></a>00074 <span class="comment"> * Remove named resource associated with a shared memory segment,</span> <a name="l00075"></a>00075 <span class="comment"> * preventing attachments to the resource, but not destroying it.</span> <a name="l00076"></a>00076 <span class="comment"> * @param filename The filename associated with shared-memory segment which</span> <a name="l00077"></a>00077 <span class="comment"> * needs to be removed</span> <a name="l00078"></a>00078 <span class="comment"> * @param pool The pool used for file operations</span> <a name="l00079"></a>00079 <span class="comment"> * @remark This function is only supported on platforms which support</span> <a name="l00080"></a>00080 <span class="comment"> * name-based shared memory segments, and will return APR_ENOTIMPL on</span> <a name="l00081"></a>00081 <span class="comment"> * platforms without such support. Removing the file while the shm</span> <a name="l00082"></a>00082 <span class="comment"> * is in use is not entirely portable, caller may use this to enhance</span> <a name="l00083"></a>00083 <span class="comment"> * obscurity of the resource, but be prepared for the the call to fail,</span> <a name="l00084"></a>00084 <span class="comment"> * and for concurrent attempts to create a resource of the same name</span> <a name="l00085"></a>00085 <span class="comment"> * to also fail. The pool cleanup of apr_shm_create (apr_shm_destroy)</span> <a name="l00086"></a>00086 <span class="comment"> * also removes the named resource.</span> <a name="l00087"></a>00087 <span class="comment"> */</span> <a name="l00088"></a>00088 <a class="code" href="group__apr__platform.html#gad7b91b811a172bfa802603c2fb688f98">APR_DECLARE</a>(<a class="code" href="group__apr__errno.html#gaf76ee4543247e9fb3f3546203e590a6c">apr_status_t</a>) <a class="code" href="group__apr__shm.html#gaee8b7d9b952ff6157ddbb00fabb477e0">apr_shm_remove</a>(const <span class="keywordtype">char</span> *filename, <a name="l00089"></a>00089 <a class="code" href="group__apr__pools.html#gaf137f28edcf9a086cd6bc36c20d7cdfb">apr_pool_t</a> *pool); <a name="l00090"></a>00090 <span class="comment"></span> <a name="l00091"></a>00091 <span class="comment">/**</span> <a name="l00092"></a>00092 <span class="comment"> * Destroy a shared memory segment and associated memory.</span> <a name="l00093"></a>00093 <span class="comment"> * @param m The shared memory segment structure to destroy.</span> <a name="l00094"></a>00094 <span class="comment"> */</span> <a name="l00095"></a>00095 <a class="code" href="group__apr__platform.html#gad7b91b811a172bfa802603c2fb688f98">APR_DECLARE</a>(<a class="code" href="group__apr__errno.html#gaf76ee4543247e9fb3f3546203e590a6c">apr_status_t</a>) <a class="code" href="group__apr__shm.html#ga7de5b65a9c7d9840bfa289854f8d59d4">apr_shm_destroy</a>(<a class="code" href="group__apr__shm.html#ga79e8c16bdeaf7ade4ef0f935249e7c2f">apr_shm_t</a> *m); <a name="l00096"></a>00096 <span class="comment"></span> <a name="l00097"></a>00097 <span class="comment">/**</span> <a name="l00098"></a>00098 <span class="comment"> * Attach to a shared memory segment that was created</span> <a name="l00099"></a>00099 <span class="comment"> * by another process.</span> <a name="l00100"></a>00100 <span class="comment"> * @param m The shared memory structure to create.</span> <a name="l00101"></a>00101 <span class="comment"> * @param filename The file used to create the original segment.</span> <a name="l00102"></a>00102 <span class="comment"> * (This MUST match the original filename.)</span> <a name="l00103"></a>00103 <span class="comment"> * @param pool the pool from which to allocate the shared memory</span> <a name="l00104"></a>00104 <span class="comment"> * structure for this process.</span> <a name="l00105"></a>00105 <span class="comment"> */</span> <a name="l00106"></a>00106 <a class="code" href="group__apr__platform.html#gad7b91b811a172bfa802603c2fb688f98">APR_DECLARE</a>(<a class="code" href="group__apr__errno.html#gaf76ee4543247e9fb3f3546203e590a6c">apr_status_t</a>) <a class="code" href="group__apr__shm.html#ga0e542941c280cb72b78e30d452464759">apr_shm_attach</a>(<a class="code" href="group__apr__shm.html#ga79e8c16bdeaf7ade4ef0f935249e7c2f">apr_shm_t</a> **m, <a name="l00107"></a>00107 const <span class="keywordtype">char</span> *filename, <a name="l00108"></a>00108 <a class="code" href="group__apr__pools.html#gaf137f28edcf9a086cd6bc36c20d7cdfb">apr_pool_t</a> *pool); <a name="l00109"></a>00109 <span class="comment"></span> <a name="l00110"></a>00110 <span class="comment">/**</span> <a name="l00111"></a>00111 <span class="comment"> * Detach from a shared memory segment without destroying it.</span> <a name="l00112"></a>00112 <span class="comment"> * @param m The shared memory structure representing the segment</span> <a name="l00113"></a>00113 <span class="comment"> * to detach from.</span> <a name="l00114"></a>00114 <span class="comment"> */</span> <a name="l00115"></a>00115 <a class="code" href="group__apr__platform.html#gad7b91b811a172bfa802603c2fb688f98">APR_DECLARE</a>(<a class="code" href="group__apr__errno.html#gaf76ee4543247e9fb3f3546203e590a6c">apr_status_t</a>) <a class="code" href="group__apr__shm.html#ga900095a06d3fdb4cdd04ca4449a9d42a">apr_shm_detach</a>(<a class="code" href="group__apr__shm.html#ga79e8c16bdeaf7ade4ef0f935249e7c2f">apr_shm_t</a> *m); <a name="l00116"></a>00116 <span class="comment"></span> <a name="l00117"></a>00117 <span class="comment">/**</span> <a name="l00118"></a>00118 <span class="comment"> * Retrieve the base address of the shared memory segment.</span> <a name="l00119"></a>00119 <span class="comment"> * NOTE: This address is only usable within the callers address</span> <a name="l00120"></a>00120 <span class="comment"> * space, since this API does not guarantee that other attaching</span> <a name="l00121"></a>00121 <span class="comment"> * processes will maintain the same address mapping.</span> <a name="l00122"></a>00122 <span class="comment"> * @param m The shared memory segment from which to retrieve</span> <a name="l00123"></a>00123 <span class="comment"> * the base address.</span> <a name="l00124"></a>00124 <span class="comment"> * @return address, aligned by APR_ALIGN_DEFAULT.</span> <a name="l00125"></a>00125 <span class="comment"> */</span> <a name="l00126"></a>00126 <a class="code" href="group__apr__platform.html#gad7b91b811a172bfa802603c2fb688f98">APR_DECLARE</a>(<span class="keywordtype">void</span> *) <a class="code" href="group__apr__shm.html#gade739e1f5f4e88c93256a63ebfd47d4d">apr_shm_baseaddr_get</a>(const <a class="code" href="group__apr__shm.html#ga79e8c16bdeaf7ade4ef0f935249e7c2f">apr_shm_t</a> *m); <a name="l00127"></a>00127 <span class="comment"></span> <a name="l00128"></a>00128 <span class="comment">/**</span> <a name="l00129"></a>00129 <span class="comment"> * Retrieve the length of a shared memory segment in bytes.</span> <a name="l00130"></a>00130 <span class="comment"> * @param m The shared memory segment from which to retrieve</span> <a name="l00131"></a>00131 <span class="comment"> * the segment length.</span> <a name="l00132"></a>00132 <span class="comment"> */</span> <a name="l00133"></a>00133 <a class="code" href="group__apr__platform.html#gad7b91b811a172bfa802603c2fb688f98">APR_DECLARE</a>(apr_size_t) <a class="code" href="group__apr__shm.html#ga557ae85d3f225620a77ad80caeaacac7">apr_shm_size_get</a>(const <a class="code" href="group__apr__shm.html#ga79e8c16bdeaf7ade4ef0f935249e7c2f">apr_shm_t</a> *m); <a name="l00134"></a>00134 <span class="comment"></span> <a name="l00135"></a>00135 <span class="comment">/**</span> <a name="l00136"></a>00136 <span class="comment"> * Get the pool used by this shared memory segment.</span> <a name="l00137"></a>00137 <span class="comment"> */</span> <a name="l00138"></a>00138 <a class="code" href="group__apr__pools.html#ga89ce1d55c7f0c39ea87c88eabd655394">APR_POOL_DECLARE_ACCESSOR</a>(shm); <a name="l00139"></a>00139 <span class="comment"></span> <a name="l00140"></a>00140 <span class="comment">/** @} */</span> <a name="l00141"></a>00141 <a name="l00142"></a>00142 <span class="preprocessor">#ifdef __cplusplus</span> <a name="l00143"></a>00143 <span class="preprocessor"></span>} <a name="l00144"></a>00144 <span class="preprocessor">#endif</span> <a name="l00145"></a>00145 <span class="preprocessor"></span> <a name="l00146"></a>00146 <span class="preprocessor">#endif </span><span class="comment">/* APR_SHM_T */</span> </pre></div></div> <!--- window showing the filter options --> <div id="MSearchSelectWindow" onmouseover="return searchBox.OnSearchSelectShow()" onmouseout="return searchBox.OnSearchSelectHide()" onkeydown="return searchBox.OnSearchSelectKey(event)"> <a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(0)"><span class="SelectionMark"> </span>All</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(1)"><span class="SelectionMark"> </span>Data Structures</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(2)"><span class="SelectionMark"> </span>Files</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(3)"><span class="SelectionMark"> </span>Functions</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(4)"><span class="SelectionMark"> </span>Variables</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(5)"><span class="SelectionMark"> </span>Typedefs</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(6)"><span class="SelectionMark"> </span>Enumerations</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(7)"><span class="SelectionMark"> </span>Enumerator</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(8)"><span class="SelectionMark"> </span>Defines</a></div> <!-- iframe showing the search results (closed by default) --> <div id="MSearchResultsWindow"> <iframe src="" frameborder="0" name="MSearchResults" id="MSearchResults"> </iframe> </div> <hr class="footer"/><address style="text-align: right;"><small>Generated on Tue Feb 14 10:09:01 2012 for Apache Portable Runtime by <a href="http://www.doxygen.org/index.html"> <img class="footer" src="doxygen.png" alt="doxygen"/></a> 1.6.3 </small></address> </body> </html>