note 118495 added to function.shell-exec

To run a command in background, the output must be redirected to /dev/null. This is written in exec() manual page. There are cases where you need the output to be logged somewhere else though. Redirecting the output to a file like this didn't work for me: <?php # this doesn't work! shell_exec("my_script.sh 2>&1 >> /tmp/mylog &"); ?> Using the above command still hangs web browser request. Seems like you have to add exactly "/dev/null" to the command line. For instance, this worked: <?php # works, but output is lost shell_exec("my_script.sh 2>/dev/null >/dev/null &"); ?> But I wanted the output, so I used this: <?php shell_exec("my_script.sh 2>&1 | tee -a /tmp/mylog 2>/dev/null >/dev/null &"); ?> Hope this helps someone. ---- Server IP: 72.52.91.14 Probable Submitter: 189.30.193.215 ---- Manual Page -- http://php.net/manual/en/function.shell-exec.php Edit -- https://master.php.net/note/edit/118495 Del: integrated -- https://master.php.net/note/delete/118495/integrated Del: useless -- https://master.php.net/note/delete/118495/useless Del: bad code -- https://master.php.net/note/delete/118495/bad+code Del: spam -- https://master.php.net/note/delete/118495/spam Del: non-english -- https://master.php.net/note/delete/118495/non-english Del: in docs -- https://master.php.net/note/delete/118495/in+docs Del: other reasons-- https://master.php.net/note/delete/118495 Reject -- https://master.php.net/note/reject/118495 Search -- https://master.php.net/manage/user-notes.php