The "cat1" is from perldoc IPC::Run, and runs as expected when using cat as the child (I get back on stdout what I used for input). When I use my "wr2" script as the child I get nothing on the parent's stdout. When I use "wr2" separately on the command line I get what I expect:

$ echo 123123 | wr2
123123
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I've googled at great length, but all the examples are about being the parent, not being the child.

This is cat1:

#!/usr/bin/perl

use warnings;
use strict;

use IPC::Run qw(start pump finish timeout);

#my @cat = qw(/bin/cat);
my @cat = qw(/home/cwood/bin/wr2);

my ($in, $out, $err);

my $h = start \@cat, \$in, \$out, \$err, timeout(10);

$in .= "some input\n";
pump $h until $out =~ /input\n/g;

$in .= "some more input\n";
pump $h until $out =~ /\G.*more input\n/;

$in .= "some final input\n";
finish $h or die "cat returned $?";

warn $err if $err;
print $out;    ## All of cat's output
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This is wr2:

#!/usr/bin/perl

use warnings;
use strict;

while (<STDIN>) {
    print;
}
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