#!/usr/bin/perl
# vi:ts=4 sw=4 et:
use strict;
use warnings;

my $compiler = 'g++';
my $file_in  = shift @ARGV;
my $file_out = shift @ARGV;

my $out = qx( $compiler $file_in -o $file_out );

print ">>>$out\nLength: ", length( $out ), "\n";

$ perl cp.pl a.c r.x
a.c: In function ‘int main()’:
a.c:4: error: ‘it’ was not declared in this scope
a.c:4: error: expected `;' before ‘i’
a.c:5: error: ‘i’ was not declared in this scope
>>>
Length: 0