这两个函数都是执行Linux命令函数,不同的是获取返回结果不一样,exec只能获取最后一行数据,shell_execu则可以获取全部数据。
假如脚本路径下有如下文件:
-bash-4.1# ll
总用量 12
-rw-rw-r--. 1 www web 133 7月 16 15:00 a.php
-rw-r--r--. 1 lee web 59 2月 29 17:05 b.php
-rw-r--r--. 1 lee web 81 3月 8 17:00 c.php
exec例子
/**
* exec与shell_exec的区别
* 琼台博客
*/
$data = exec('/bin/ls -l');
echo '
';<br> print_r($data);<br> echo '';
?>
执行结果
-rw-r--r--. 1 lee web 81 Mar 8 17:00 c.php
shell_exec例子
/**
* exec与shell_exec的区别
* 琼台博客
*/
$data = shell_exec('/bin/ls -l');
echo '
';<br> print_r($data);<br> echo '';
?>
执行结果
total 12
-rw-rw-r--. 1 www web 139 Jul 16 2012 a.php
-rw-r--r--. 1 lee web 59 Feb 29 17:05 b.php
-rw-r--r--. 1 lee web 81 Mar 8 17:00 c.php
所以平时使用exec函数的童鞋注意了,如果你需要获取全部返回信息,就应该使用shell_exec函数,当然,如果命令执行结果只有一行返回信息,那么使用哪个都无所谓。

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