Question

How would I execute a shell script from PHP while giving constant/live feedback to the browser?
I understand from the system function documentation:

The system() call also tries to automatically flush the web server’s
output buffer after each line of output if PHP is running as a server
module.

I’m not clear on what they mean by running it as a ‘server module’.

Example PHP code:

<?php

system('/var/lib/script_test.sh');

Example shell code:

#!/bin/bash

echo "Start..."
for i in {1..10}
do
        echo "$i..."
        sleep 1
done
echo "Done."

What this does: It will wait about 10 seconds and then flush to the output buffer.

What I want this to do: Flush to the output buffer after each line of output.

Answer 1

This can be done using popen() which gives you a handle to the stdout of whatever process you open. Chunks of data can be sent to the client using ob_flush(), the data can be displayed using an XHR.