PHP：为什么 exec() 不返回输出？
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PHP: Why isn't exec() returning output?
提问by Edward
I'm writing a PHP script to be used to check for network connections with Linux shell command pingcalling it with PHP's exec():
我正在编写一个 PHP 脚本，用于使用 Linux shell 命令检查网络连接，ping并使用 PHP 调用它exec()：
<?php
// Bad IP domain for testing.
$domain_bad = "lksjdflksjdf.com";
$ip_address = $domain_bad;
exec("ping -c 1 $domain_bad", $output, $return_var);
var_dump($return_var);
echo "return_var is: $return_var" . "\n";
var_dump($output);
exit;
?>
I'm not getting the output for the error message from ping in $outputwhich is what I'm expecting:
我没有从 ping 中获得错误消息的输出，$output这正是我所期望的：
$ php try.php
ping: unknown host lksjdflksjdf.com
int(2)
return_var is: 2
array(0) {
}
If the domain is a good domain, such as yahoo.com, then $outputhas the output from ping in an array. But if it's an error such as 'ping: unknown host lksjdflksjdf.com'it doesn't get returned to the $outputarray.
如果该域是一个好的域，例如 yahoo.com，则$outputping 的输出在一个数组中。但是如果它是一个错误，例如'ping: unknown host lksjdflksjdf.com'它不会返回到$output数组中。
Why is this happening and is there a better method to do this?
为什么会发生这种情况，是否有更好的方法来做到这一点？
回答by Hariprasad
回答by Ph?m Tu?n Anh
If the answer above could not solve your problem, maybe exec()is disabled. You can try to check php.inifile at disable_functionsline.
如果上述答案无法解决您的问题，则可能exec()已禁用。您可以尝试在线检查php.ini文件disable_functions。
