zip_via_system.php

<?php
function liveExecuteCommand($cmd)
{

    while (@ ob_end_flush()); // end all output buffers if any

    $proc = popen("$cmd 2>&1 ; echo Exit status : $?", 'r');

    $live_output     = "";
    $complete_output = "";

    while (!feof($proc))
    {
        $live_output     = fread($proc, 4096);
        $complete_output = $complete_output . $live_output;
        echo str_replace("\n","<br>", $live_output);
        @ flush();
    }

    pclose($proc);

    // get exit status
    preg_match('/[0-9]+$/', $complete_output, $matches);

    // return exit status and intended output
    return array (
                    'exit_status'  => intval($matches[0]),
                    'output'       => str_replace("Exit status : " . $matches[0], '', $complete_output)
                 );
}

echo "<code>";
$command='zip -r ../html.zip ./';
$result = liveExecuteCommand($command);
echo "</code>";
echo "<hr>";
if($result['exit_status'] === 0){
   echo "execution OK.";
} else {
    echo "execution FAILED!";
}