我需要测试一些phpcli脚本，该脚本使用stdout、stderr并返回错误代码。
- exec似乎不返回stderr
- 系统不返回stdout（仅返回最后一行），stderr
proc_open。
文件：script.php
echo 'Standart output'; //stdout
error_log('Error output'); //stderr
exit(1); //return
文件：test.php
<?php
$descriptorspec = array(
1 => array("pipe", "w"), // stdout is a pipe that the child will write to
2 => array("pipe", "w") // stderr is a pipe that the child will write to
);
$process = proc_open('php script.php', $descriptorspec, $pipes);
if (is_resource($process))
{
echo 'stdout: ' . stream_get_contents($pipes[1]) . PHP_EOL;
fclose($pipes[1]);
echo 'stderr: ' . stream_get_contents($pipes[2]) . PHP_EOL;
fclose($pipes[2]);
$return_value = proc_close($process);
echo 'return: ' . $return_value . PHP_EOL;
}