php exec() background process issues

Question

I\'m trying to process a file in the background with the following command, but it does nothing.

exec(\"php csv.php $file $user > /dev/null &\", $outp         


        

Answer 1

Have you considered using screen? You can start up a screen session that runs in a detached process. Output will go to the screen session, which you can reattach to in another terminal while it is still running.

exec("screen -d -m -S my_php_session csv.php $file $user", $output);

Answer 2

Note:

If a program is started with this function, in order for it to continue running in the background, the output of the program must be redirected to a file or another output stream. Failing to do so will cause PHP to hang until the execution of the program ends.

http://php.net/manual/en/function.exec.php

so:

exec("php csv.php $file $user > /dev/null &"); // no $output