use IPC::Open3;
use POSIX ":sys_wait_h";
package SysCall3;
sub exec{
    my $self = shift;
    my $command = shift;
    $self = {};
    my $pid = open3 my $wh, my $rh, my $eh, $command;
    $self -> { EXITCODE } = $?;
    close $wh;
    $self -> { STDOUT } = <$rh>;
    close $rh;
    $self -> { STDERR } = <$eh>;
    close $eh;
    waitpid $pid,0;
    return bless $self;
}
sub getinfo(
    my $self = shift;
    return $self -> { shift() };
}
1;
##</code><code>##

use SysCall3;
my $nasty = SysCall3 -> exec( 'bigNastyProgram' );
for my $err ( $nasty -> getinfo( 'STDERR' ) ) {
    # process the error output
    print STDERR $err;
}
for my $out ( $nasty -> getinfo ('STDOUT' ) ) {
    # process the stdout
    print $out;
}
my $code = $nasty -> getinfo( 'EXITCODE' );
# process return code
exit $code; # if wanting to pass control back to the o/s