Difference between exec function and shell_exec function in PHP

These two functions are functions that execute Linux command. The difference is that the return results are different. exec can only get the last row of data, while shell_execu can get all the data.

Suppose there are the following files under the script path:

-bash-4.1# ll

 Total dosage  12

-rw-rw-r--. 1 www web 133  7 Month  16 15:00 a.php

-rw-r--r--. 1 lee web  59  2 Month  29 17:05 b.php

-rw-r--r--. 1 lee web  81  3 Month   8 17:00 c.php

exec Example

<?php

/**

 * exec And shell_exec Difference between 

 *  Qiongtai blog 

 */

$data = exec('/bin/ls -l');

echo '<pre>';

print_r($data);

echo '</pre>';

?>

Execution results

-rw-r--r--. 1 lee web  81 Mar  8 17:00 c.php

shell_exec Example

<?php

/**

 * exec And shell_exec Difference between 

 *  Qiongtai blog 

 */

$data = shell_exec('/bin/ls -l');

echo '<pre>';

print_r($data);

echo '</pre>';

?>

Execution results

 

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

Therefore, children who usually use exec function should pay attention. If you need to get all the return information, you should use shell_exec function. Of course, if the command execution result only has 1 line of return information, it doesn't matter which one you use.