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pcntl_exec

(PHP 4 >= 4.2.0, PHP 5, PHP 7, PHP 8)

pcntl_exec現在のプロセス空間で指定したプログラムを実行する

説明

pcntl_exec(string $path, array $args = [], array $env_vars = []): bool

指定した引数でプログラムを実行します。

パラメータ

path

path は、バイナリ実行ファイルへのパスか、 あるいは有効な実行ファイルを指す shebang (例: #!/usr/local/bin/perl) が一行目に存在するスクリプトへのパスである必要があります。 詳細な情報については、システムの man ページで execve(2) を参照ください。

args

args は、プログラムに渡す引数文字列の配列です。

env_vars

env_vars は、プログラムに渡す環境変数の配列です。 この配列は name => value のような形式で、key が環境変数名・value が その値となります。

戻り値

Returns false.

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User Contributed Notes 3 notes

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12
eric kilfoil
17 years ago
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.
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10
agodong at verizon dot net
17 years ago
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.
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3
rbemrose at vgmusic dot com
16 years ago
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.
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