I'm attempting to write a wrapper for some external programs that I'll be calling from a Perl script.

I need to capture all the inputs and outputs - STDERR being the most important.

After looking through The Camel and around the Monastery, I found IPC::Open3.

I've already looked at the following nodes, but I'm still unable to get a script that performs as I expect:

• Open3 and bad gut feeling
• once again: program output and return code (my question seems to be very similar to particle's).

For testing purposes I'm just using a simple Perl script as the command to be run by open3(), rather than using the binary. I've also tried using cat as well.
This script is as follows:

#!/usr/local/bin/perl

# Test script to write to STDOUT
# and STDERR.

use warnings;
use strict;

print STDOUT "StdOut!\n";
print STDERR "StdErr!\n";
[download]

The main script (using IPC::Open3) is:

#!/usr/local/bin/perl

# Script to test IPC::Open3
# Runs, displays $pid to STDOUT, but opened
# files are empty.

use strict;
use warnings;
use diagnostics;
use IPC::Open3;

$|++;

my $cmd = "/home/baz/test.pl";

open(ERRLOG, ">error.log") or die "Can't open error log! $!";
open(OUTPUT, ">output.log") or die "Can't open output log! $!";

my $pid = open3(\*STDIN, \*OUTPUT, \*ERRLOG, $cmd) or die "$!";

print "PID was $pid\n";

close(ERRLOG) or die "Can't close filehandle! $!";
close(OUTPUT) or die "Can't close filehandle! $!";
[download]

I'm expecting this script to write the output from my test.pl script to output.log and errors from the test script to error.log, however both files are created, but empty.

Have I got the wrong end of the stick somewhere?

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