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POHow to communicate between php and boost library IPC?
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  1. POHow to communicate between php and boost library IPC?
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    copied!<p>I have client and server in php communicating over shared memory, Now I would like to access this shred memory object using Boost.Interprocess how can I access it? server.php:</p> <pre><code> function create_image($str){ // Create a blank image and add some text $im = imagecreatetruecolor(300, 20); $text_color = imagecolorallocate($im, 233, 14, 91); $stringBanner=exec("date").$str; imagestring($im, 1, 5, 5, $stringBanner , $text_color); ob_start(); imagejpeg($im); $i = ob_get_contents(); ob_get_clean(); imagedestroy($im); return $i; } echo "\n".__FILE__."\n"; $shm_key = ftok(__FILE__, 't'); echo $shm_key."\n"; $shm_id = shmop_open($shm_key, "a", 0, 0); if ($shm_id) { //it is already created shmop_delete($shm_id); shmop_close($shm_id); } //you need to create it with shmop_open using "c" only echo "try to create\n"; if(!$shm_id = shmop_open($shm_key, "c", 0777, 1024*4))exit(-1); echo "ID ".$shm_id."\n"; $i=0; for(;;){ sleep(1); $s="i=".$i++; $str=$i; $im=serialize(create_image($str)); $data=serialize(strlen($im)); $shm_bytes_written = shmop_write($shm_id, $data, 0); $shm_bytes_written = shmop_write($shm_id, $im, 32); echo $shm_bytes_written." bytes is written: ".$s." ID = $shm_id\n"; } </code></pre> <p>client.php</p> <pre><code>&lt;?php $shm_key =1946222626;// ftok(__FILE__, 't'); $shm_id = shmop_open( $shm_key, "a", 0644,1024*4 ); $s=shmop_size($shm_id); $data = unserialize( shmop_read( $shm_id, 0, 31) ); $im = unserialize( shmop_read( $shm_id, 32, $data) ); // Set the content type header - in this case image/jpeg header('Content-Type: image/jpeg'); // Output the image echo $im; </code></pre> <p>What kind of key I should provide to Boost to get this memory region?</p> <p>boost_client.cpp</p> <pre><code>#include &lt;boost/interprocess/shared_memory_object.hpp&gt; #include &lt;iostream&gt; #include "sys/msg.h" int main() { int msqid; key_t key; char f[]="??????"; int mid; //key = ftok(, 't'); //msqid = msgget(key, 0666 | IPC_CREAT); std::cout&lt;&lt;msqid&lt;&lt;std::endl; boost::interprocess::shared_memory_object shdmem(boost::interprocess::open_or_create, f,//"shmem_server", boost::interprocess::read_write); shdmem.truncate(1024); std::cout &lt;&lt; shdmem.get_name() &lt;&lt; std::endl; boost::interprocess::offset_t size; if (shdmem.get_size(size)) std::cout &lt;&lt; size &lt;&lt; std::endl; } </code></pre> <p><strong>EDIT:</strong></p> <p>Well I found the solution in Boost IPC library Docs:</p> <p><a href="http://www.boost.org/doc/libs/1_49_0/doc/html/interprocess/sharedmemorybetweenprocesses.html#interprocess.sharedmemorybetweenprocesses.sharedmemory.xsi_shared_memory">XSI_KEY based example from boost Docs</a></p>
 

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