note 22204 added to function.shell-exec

I tried shell_exec(), backtick operator and system() to execute a shell script (in RedHat Linux 7.0, using Apache server), that works correctly from the command line, and it doesn't work when executed from a PHP script. I also tried to redirect the output to a file in /var/www/html and if I create the file it does not write anything into it,although from the command line it works. I don't understand the problem, because the PHP script executes, for example, the ls command, and returns the result in the page. Do you have any ideas about what's going on? Can you please help me? -- http://www.php.net/manual/en/function.shell-exec.php http://master.php.net/manage/user-notes.php?action=edit+22204 http://master.php.net/manage/user-notes.php?action=delete+22204 http://master.php.net/manage/user-notes.php?action=reject+22204