pcntl_alarm
I spent a lot of time trying to figure this powerful option out so I didn't get error 2 or error 8. The documentation says it can execute a binary file and here is a good example that works that I found;
<?php
print "Before\\n";
pcntl_exec("/usr/bin/uptime");
print "After\\n";
?>
However I wanted it to run another php program and after wasting a lot of time I finally got it.
<?php
$tasks2=array('/var/www/example.php');
pcntl_exec("/usr/bin/php",$tasks2);
?>
The php script has to be in an array and you execute the binary php file
I'll be adding this to launching a child and run it seperately using this function
<?php
function launchchild($programexe,$programvars)
{
//foreach ($tasks as $key => $v){
switch ($pid = pcntl_fork()) {
case -1:
// @fail
die('Fork failed');
break;
case 0:
// @child: Include() misbehaving code here
print "FORK: Child #{$x} \\n";
echo "child after fork:", getmypid(), PHP_EOL;
pcntl_exec($programexe,$programvars);
// generate_fatal_error(); // Undefined function
break;
default:
// @parent
print "FORK: $x Parent\\n";
echo "parent after fork:", getmypid(), PHP_EOL;
// pcntl_waitpid($pid, $status);
break;
}
print "Done! :^)\\n\\n";
}
?>
pcntl_exec
(PHP 4 >= 4.2.0, PHP 5)
pcntl_exec — 在当前进程空间执行指定程序
说明
void pcntl_exec
( string
$path
[, array $args
[, array $envs
]] )以给定参数执行程序。
参数
-
path -
path必须时可执行二进制文件路径或一个在文件第一行指定了 一个可执行文件路径标头的脚本（比如文件第一行是#!/usr/local/bin/perl的perl脚本）。 更多的信息请查看您系统的execve（2）手册。 -
args -
args是一个要传递给程序的参数的字符串数组。 -
envs -
envs是一个要传递给程序作为环境变量的字符串数组。这个数组是 key => value格式的，key代表要传递的环境变量的名称，value代表该环境变量值。
返回值
当发生错误时返回 FALSE ，没有错误时没有返回。
add a note
User Contributed Notes
pcntl_exec
trevorpearce at gmail dot com
22-Jan-2012 11:36
fahadsadah at gmail dot com dot please dot remove dot this
28-Jun-2008 01:44
Just a note regarding what rbemrose at vgmusic dot com said:
Once the executed process ends, control returns to the webserver process.
rbemrose at vgmusic dot com
06-Feb-2008 07:44
As a side note, if I'm reading the comments below correctly, you should not run this if you're using a PHP webserver module, as it will replace the webserver's process with whatever process you're telling it to run.
agodong at verizon dot net
07-Dec-2006 03:47
Some people might find it useful to run other program using the same process as a different user. This is very usefull if the script is running under root. Here is a simple code to achieve that under *nix PHP CLI:
#!/usr/bin/php -q
<?php
//Enter run-as user below (argument needed to be passed when the script is called), otherwise it will run as the caller user process.
$username = $_SERVER['argv'][1];
$user = posix_getpwnam($username);
posix_setuid($user['uid']);
posix_setgid($user['gid']);
pcntl_exec('/path/to/cmd');
?>
I use this as a part of socket program so that a program can be run under different user from remote location.
eric kilfoil
24-Oct-2006 04:01
The pcntl_exec() function works exactly like the standard (unix-style) exec() function. It differs from the regular PHP exec() function in that the process calling the pcntl_exec() is replaced with the process that gets called. This is the ideal method for creating children. In a simple example (that does no error checking):
switch (pcntl_fork()) {
case 0:
$cmd = "/path/to/command";
$args = array("arg1", "arg2");
pcntl_exec($cmd, $args);
// the child will only reach this point on exec failure,
// because execution shifts to the pcntl_exec()ed command
exit(0);
default:
break;
}
// parent continues
echo "I am the parent";
--
since this is not being executed through a shell, you must provide the exact path from the filesystem root. Look at the execve() man page for more information.
michael dot ferre at mobileway dot com
19-Nov-2002 08:28
//To complete my last note
//If you use some object in your php code
//You will have some problem if you do a exit after include the
//child scripts
//You must use posix_kill() like that :
$CHILD_PID = pcntl_fork();
if($CHILD_PID == 0)
{
include ($script_path);
posix_kill(getmypid(),9);
}
//This code is very simple it can be ameliorate ;)
michael dot ferre at mobileway dot com
18-Nov-2002 09:19
//If you are in php version between 4.1 and 4.2
//When you use pcntl_fork and after you want use
//pcntl_exec, you can because pcntl_exec isn't used before
//php 4.2 so let me show a solution :
$CHILD_PID = pcntl_fork();
if($CHILD_PID == 0)
{
include ($script_path);
exit;
}
//$script_path is the *.php page which you want lauch like
// a child .
//I don't know why php coder hadn't add pcntl_exec in the
//same time that other function
//Michal F. php developer .