#!/usr/bin/perl

    use strict;
    use warnings;

    use File::Copy;

    umask 022 or die "umask: $!";
    
    my $one   = "/tmp/one";
    my $two   = "/tmp/two";
    my $three = "/tmp/three";

    foreach my $file ($one, $two, $three) {
        ! -f $file or unlink $file or die "unlink $file: $!"  
    }

    # Create first file.
    open my $fh, "> $one" or die "one: $!";
    close $fh;

    # Make it executable.
    chmod 0755 => $one or die "chmod: $!";

    # Copy it with File::Copy.
    copy $one, $two or die "copy: $!";
    # Copy using the UNIX toolkit.
    system cp => $one, $three;
    die "cp: ", $? >> 8 if $?;
   
    # And check.
    print "$one is executable\n"   if -x $one;
    print "$two is executable\n"   if -x $two;
    print "$three is executable\n" if -x $three;
    __END__
    /tmp/one is executable
    /tmp/three is executable