#!/usr/bin/perl

@callout = qw( echo foo );

open(my $old_stdout,">&STDOUT");
close(STDOUT);
my $stdout;
open(STDOUT,">",\$stdout);

my $system_return_value = system(@callout);

close(STDOUT);
open(STDOUT,">&",$old_stdout);
close($old_stdout);

print "captured: $stdout\n"; # debug

unless ( $system_return_value == 0 ) {
#... do some stuff, look at return code (shift by 8), 
# print stdout/stderr of 
# failed command to log, etc, etc.
}