<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> <title>Copy data from named shared memory</title> </head> <body><div class="manualnavbar" style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="syncsharedmemory.first.html">SyncSharedMemory::first</a></div> <div class="next" style="text-align: right; float: right;"><a href="syncsharedmemory.size.html">SyncSharedMemory::size</a></div> <div class="up"><a href="class.syncsharedmemory.html">SyncSharedMemory</a></div> <div class="home"><a href="index.html">PHP Manual</a></div> </div><hr /><div id="syncsharedmemory.read" class="refentry"> <div class="refnamediv"> <h1 class="refname">SyncSharedMemory::read</h1> <p class="verinfo">(PECL sync >= 1.1.0)</p><p class="refpurpose"><span class="refname">SyncSharedMemory::read</span> — <span class="dc-title">Copy data from named shared memory</span></p> </div> <div class="refsect1 description" id="refsect1-syncsharedmemory.read-description"> <h3 class="title">Description</h3> <div class="methodsynopsis dc-description"> <span class="modifier">public</span> <span class="methodname"><strong>SyncSharedMemory::read</strong></span> ([ <span class="methodparam"><span class="type">int</span> <code class="parameter">$start</code><span class="initializer"> = 0</span></span> [, <span class="methodparam"><span class="type">int</span> <code class="parameter">$length</code></span> ]] )</div> <p class="para rdfs-comment"> Copies data from named shared memory. </p> </div> <div class="refsect1 parameters" id="refsect1-syncsharedmemory.read-parameters"> <h3 class="title">Parameters</h3> <dl> <dt> <code class="parameter">start</code></dt> <dd> <p class="para"> The start/offset, in bytes, to begin reading. </p> <blockquote class="note"><p><strong class="note">Note</strong>: <p class="para"> If the value is negative, the starting position will begin at the specified number of bytes from the end of the shared memory segment. </p> </p></blockquote> </dd> <dt> <code class="parameter">length</code></dt> <dd> <p class="para"> The number of bytes to read. </p> <blockquote class="note"><p><strong class="note">Note</strong>: <p class="para"> If unspecified, reading will stop at the end of the shared memory segment. </p> <p class="para"> If the value is negative, reading will stop the specified number of bytes from the end of the shared memory segment. </p> </p></blockquote> </dd> </dl> </div> <div class="refsect1 returnvalues" id="refsect1-syncsharedmemory.read-returnvalues"> <h3 class="title">Return Values</h3> <p class="para"> A string containing the data read from shared memory. </p> </div> <div class="refsect1 examples" id="refsect1-syncsharedmemory.read-examples"> <h3 class="title">Examples</h3> <div class="example" id="example-4608"> <p><strong>Example #1 <span class="function"><a href="syncsharedmemory.construct.html" class="function">SyncSharedMemory::__construct()</a></span> example</strong></p> <div class="example-contents"> <div class="phpcode"><code><span style="color: #000000"> <span style="color: #0000BB"><?php<br /></span><span style="color: #FF8000">// You will probably need to protect shared memory with other synchronization objects.<br />// Shared memory goes away when the last reference to it disappears.<br /></span><span style="color: #0000BB">$mem </span><span style="color: #007700">= new </span><span style="color: #0000BB">SyncSharedMemory</span><span style="color: #007700">(</span><span style="color: #DD0000">"AppReportName"</span><span style="color: #007700">, </span><span style="color: #0000BB">1024</span><span style="color: #007700">);<br />if (</span><span style="color: #0000BB">$mem</span><span style="color: #007700">-></span><span style="color: #0000BB">first</span><span style="color: #007700">())<br />{<br /> </span><span style="color: #FF8000">// Do first time initialization work here.<br /></span><span style="color: #007700">}<br /><br /></span><span style="color: #0000BB">$result </span><span style="color: #007700">= </span><span style="color: #0000BB">$mem</span><span style="color: #007700">-></span><span style="color: #0000BB">write</span><span style="color: #007700">(</span><span style="color: #DD0000">"report.txt"</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">$result </span><span style="color: #007700">= </span><span style="color: #0000BB">$mem</span><span style="color: #007700">-></span><span style="color: #0000BB">read</span><span style="color: #007700">(</span><span style="color: #0000BB">3</span><span style="color: #007700">, -</span><span style="color: #0000BB">4</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$result</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?></span> </span> </code></div> </div> <div class="example-contents"><p>The above example will output something similar to:</p></div> <div class="example-contents screen"> <div class="cdata"><pre> string(3) "ort" </pre></div> </div> </div> </div> <div class="refsect1 seealso" id="refsect1-syncsharedmemory.read-seealso"> <h3 class="title">See Also</h3> <ul class="simplelist"> <li class="member"><span class="methodname"><a href="syncsharedmemory.construct.html" class="methodname" rel="rdfs-seeAlso">SyncSharedMemory::__construct()</a> - Constructs a new SyncSharedMemory object</span></li> <li class="member"><span class="methodname"><a href="syncsharedmemory.first.html" class="methodname" rel="rdfs-seeAlso">SyncSharedMemory::first()</a> - Check to see if the object is the first instance system-wide of named shared memory</span></li> <li class="member"><span class="methodname"><a href="syncsharedmemory.write.html" class="methodname" rel="rdfs-seeAlso">SyncSharedMemory::write()</a> - Copy data to named shared memory</span></li> <li class="member"><span class="methodname"><strong>SyncSharedMemory::read()</strong></span></li> </ul> </div> </div><hr /><div class="manualnavbar" style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="syncsharedmemory.first.html">SyncSharedMemory::first</a></div> <div class="next" style="text-align: right; float: right;"><a href="syncsharedmemory.size.html">SyncSharedMemory::size</a></div> <div class="up"><a href="class.syncsharedmemory.html">SyncSharedMemory</a></div> <div class="home"><a href="index.html">PHP Manual</a></div> </div></body></html>