Question

I am calling a shell script in Linux using a PHP script, I do the following:

shell_exec('./shell_script.sh');

after this the PHP script continues on.. All this works as expected.

However, sometimes the shell_script doesn’t finish executing for whatever reason, so here is the question:

How can I terminate the shell_script.sh after being executed for x amount of time?
Should this be dealt with in PHP itself somehow (dont think that’s possible in this instance) or should it be done in the .sh itself?

So just after the:

#!/bin/bash

at the beginning of the .sh, is there something I can put for it to terminate if execution time exceeds say 20 seconds perhaps?

Answer 1

I don’t know if you can do it in php, and there may exist better solutions in bash, but this is what you could do:

This is the line you can put immediately after #!/bin/bash to kill the current script after 20 seconds:

(sleep 20 && kill $$) &

bash replaces $$ with the pid of the current script.