在Perl脚本仍在运行时在浏览器中显示控制台输出

Question

Here's very simple program that I am testing on

#!/usr/bin/perl

print "This is Test Script
";
sleep(5);

print "This is Test Script
";
sleep(5);

print "This is Test Script
";
sleep(5);

print "This is Test Script
";
sleep(5);

print "This is Test Script
";
sleep(5);

print "Script Testing Done
";

Now PHP should output the script output (which is going to console) every maybe 10 seconds or 5 seconds or whenever the php sees the output on the console.

I have hundreds of perl scripts and I cannot go and change those script and direct the output to a file where php/ajax can get the content and output to the browser.

Thanks

Answer 1

You probably want proc_open() and flush().

The former allows you to read/write to processes at will. The latter flushes the output buffer.

(Edit, add example code)

Here is a sample PHP script that invokes your Perl sample above (assuming its called test.pl). Note that due to Perl's output buffering mechanism, you need to tell your Perl script to make STDOUT implicitly flush (or "make it hot" in Perl-speak). You can do this by adding $|=1 at the top of your Perl script.

<?php

$descriptor = array(
   0 => array("pipe", "r"), // stdin
   1 => array("pipe", "w"), // stdout
   2 => array("pipe", "w"), // stderr
);

$proc = proc_open('./test.pl', $descriptor, $pipes);
if ($proc) {
    fclose($pipes[0]); // no input
    stream_set_blocking($pipes[1], 0); // turn off blocking
    while (!feof($pipes[1])) {
        echo "PHP> (heartbeat)
";
        $fromPerl = fread($pipes[1], 1024); // read up to 1k
        if ($fromPerl) {
            echo "Perl> {$fromPerl}";
        }
        sleep(2); // do other work instead
    }
    proc_close($proc);
}

Here is the output:

$ time php proc.php 
PHP> (heartbeat)
PHP> (heartbeat)
Perl> This is Test Script
PHP> (heartbeat)
PHP> (heartbeat)
Perl> This is Test Script
PHP> (heartbeat)
PHP> (heartbeat)
PHP> (heartbeat)
Perl> This is Test Script
PHP> (heartbeat)
PHP> (heartbeat)
Perl> This is Test Script
PHP> (heartbeat)
PHP> (heartbeat)
PHP> (heartbeat)
Perl> This is Test Script
PHP> (heartbeat)
PHP> (heartbeat)
Perl> Script Testing Done
PHP> (heartbeat)

real    0m30.031s
user    0m0.020s
sys 0m0.018s