My open will capture both the STDERR and STDOUT messages. See below code...

Main: 

#!/usr/bin/perl
use warnings;
use strict;

open  (IN, '-|', 'perl PrintStdoutStdErr.pl') or die "$!";
while (<IN>)
{ 
    print;
}

__END__ 
prints:
this went to STDERR
this went to STDOUT

[download]
PrintStdoutStdErr.pl
#!/usr/bin/perl
use warnings;
use strict;

$|=1;

print STDOUT "this went to STDOUT\n";
print STDERR "this went to STDERR\n";

[download]
I actually wouldn't worry about Perl critic on an "ls" command.

In reply to Re^3: Using IPC::Open3 instead of backtick operator by Marshall
in thread Using IPC::Open3 instead of backtick operator by rcrews

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