proc_close
The following function takes an array of shell commands and executes them. It is able to execute up to $nb_max_process at the same time. As soon as one process is terminated, another one is executed. Quite useful if you want to batch process commands on a multi-processor or multi-core environment.
The example below tries to convert to PNG a list of SVG files submitted on the command line (using Inkscape).
(it's quick and dirty but works very well for me)
#!/usr/bin/php
<?php
function pool_execute($commandes,$nb_max_process) {
$pool=array();
for($i=0;$i<$nb_max_process;$i++) {
$pool[$i]=FALSE;
}
while(count($commandes)>0) {
$commande=array_shift($commandes);
$commande_lancee=FALSE;
while($commande_lancee==FALSE) {
usleep(50000);
for($i=0;$i<$nb_max_process and $commande_lancee==FALSE;$i++) {
if($pool[$i]===FALSE) {
$pool[$i]=proc_open($commande,array(),$foo);
$commande_lancee=TRUE;
} else {
$etat=proc_get_status($pool[$i]);
if($etat['running']==FALSE) {
proc_close($pool[$i]);
$pool[$i]=proc_open($commande,array(),$foo);
$commande_lancee=TRUE;
}
}
}
}
}
}
$fichiers=$argv;
array_shift($fichiers);
$commandes=array();
foreach($fichiers as $fichier) {
$entree=$fichier;
$sortie=basename($fichier,'.svg').".png";
$commandes[]='inkscape --file='.escapeshellarg($entree).' --export-area-canvas --export-png='.escapeshellarg($sortie);
}
pool_execute($commandes,4);
Description
array proc_get_status
( resource $process
)
proc_get_status() fetches data about a process opened using proc_open().
Return Values
An array of collected information on success, and FALSE on failure. The returned array contains the following elements:
| element | type | description |
|---|---|---|
| command | string | The command string that was passed to proc_open(). |
| pid | int | process id |
| running | bool | TRUE if the process is still running, FALSE if it has terminated. |
| signaled | bool | TRUE if the child process has been terminated by an uncaught signal. Always set to FALSE on Windows. |
| stopped | bool | TRUE if the child process has been stopped by a signal. Always set to FALSE on Windows. |
| exitcode | int | The exit code returned by the process (which is only meaningful if running is FALSE). Only first call of this function return real value, next calls return -1. |
| termsig | int | The number of the signal that caused the child process to terminate its execution (only meaningful if signaled is TRUE). |
| stopsig | int | The number of the signal that caused the child process to stop its execution (only meaningful if stopped is TRUE). |
add a note
User Contributed Notesproc_get_status
webmaster at rouen dot fr
09-Jul-2008 09:49
09-Jul-2008 09:49
strrev xc.noxeh@ellij
05-Jun-2008 09:12
05-Jun-2008 09:12
You can NOT rely on pid+1.
You could prefix exec to the command string, this will replace the /bin/sh script with the real thing you want to exec (use only if you don't do 'scary things' like pipes, output redirection, multiple commands, however if you know how they work, go ahead).
If you prefix exec, the /bin/sh process will only start your process, and the PID will be the same.
damien at cyg dot net
13-Jun-2007 02:06
13-Jun-2007 02:06
Alternatively, if you're calling a subsequent php script using proc_open, you can have that process echo its own actual PID in the output.
Also, if you go through the /proc filesystem on linux, you can read through /proc/12345 where 12345 is the pid returned by proc_get_status (the pid of the /bin/sh instance) and it will list its child processes within.
andy dot shellam at mailnetwork dot co dot uk
05-Apr-2007 01:16
05-Apr-2007 01:16
Further to my previous note, I've found out the PID returned is the PID of the shell (/bin/sh) that then runs the actual command requested.
I've raised this as bug #41003.
andy dot shellam at mailnetwork dot co dot uk
05-Apr-2007 12:58
05-Apr-2007 12:58
To the poster above, same here on FreeBSD 6.1, PHP 5.2.1.
To get the correct PID to use for posix_kill I have to add 1 to the PID returned from proc_get_status.