How to read STDOUT from a sub-process in OO Perl - perl

Question

In Perl, one way to read the STDOUT of a subprocess is to use open:
open(PIPE, "ls -l |");
I was looking for a more object-oriented way to do this, though, and I've been using IO::Pipe with some success. I want to detect errors, though, specifically if the command is not executable. I can't figure out how to do that via IO::Pipe, though. Here's what I have:
use strict;
use warnings;
use IO::Pipe;
my($cmd) = join (" ", #ARGV);
open(PIPE, "$cmd |") || die qq(error opening PIPE);
while (<PIPE>) {
chomp;
print "DBG1: $_\n";
}
close PIPE;
my($pipe) = IO::Pipe->new();
$pipe->reader($cmd);
die qq(error opening IO::Pipe) if $pipe->eof();
while (<$pipe>) {
chomp;
print "DBG2: $_\n";
}
$pipe->close();
If the sub-process command is invalid, both checks will correctly die. If the sub-process produces no output, though, eof() will report an error, even if the command itself is fine:
$ perl pipe.pl "ls -l >/dev/null"
error opening IO::Pipe at pipe.pl line 20.
A bunch of questions, then:
Is there a reasonable OO way to read from a sub-process in Perl? Is IO::Pipe the correct tool to use? If so, how do I check to make sure the sub-process command is created successfully? If not, what should I be using? I don't want to write to the sub-process, so I don't think I want IPC::Open2 or IPC::Open3. I would prefer to use a core module, if possible.

Answer 1

The issue is not IO::Pipe. The problem is eof is the wrong way to check for a pipe error. It doesn't mean there's no pipe, it means there's nothing to read from that pipe. You'd have the same problem with eof PIPE. It's perfectly fine for a sub-process to not print anything.
If you want to check the sub-process successfully ran, it turns out IO::Pipe already does that for you.
# IO::Pipe: Cannot exec: No such file or directory
$pipe->reader("hajlalglagl");

Answer 2

Backticks is not a core module but seems to do what your looking for.
use strict;
use warnings;
use Backticks;
my $cmd = Backticks->new(join (" ", #ARGV));
$cmd->run();
if ($cmd->success){
print $cmd->stdout
} else {
print "Command failed\n";
}
Running this with a valid command then invalid command gives the below results
io_pipe.pl "uname -o"
GNU/Linux
io_pipe.pl "uname -z"
Command failed
Update
As pointed out by #thisSuitIsNotBlack, this module changes the deafult behaviour of backticks in perl. You should read the Notes section of the POD. However the main one to be aware of is:
The overriding of backticks is provided by Filter::Simple. Source
filtering can be weird sometimes... if you want to use this module in
a purely traditional Perl OO style, simply turn off the source
filtering as soon as you load the module:
use Backticks;
no Backticks;