shell out to copy/cp if it's around, otherwise File::Copy

bin/cp

@@ -15,8 +15,10 @@ License: perl
 require 5;
 use strict;
 use Cwd;
+use Config;
 use File::Basename;
 use File::Find;
+use File::Spec::Functions qw(catfile);
 use Getopt::Std;
 
 #######   S U B R O U T I N E S   ###############
@@ -26,11 +28,71 @@ sub checkArgs(@);
 sub findCopy;     ## used by find()
 sub copyFile($$); ## used by find()
 
-$main::opt_f = undef;  ## used and set by getopts()
-$main::opt_i = undef;  ## used and set by getopts()
-$main::opt_p = undef;  ## used and set by getopts()
-$main::opt_v = undef;  ## used and set by getopts() not standard, but may be helpful
-                       ## especially if problems are found w/ routine.
+=pod
+
+B<-f> Force copy if possible (DEFAULT)
+
+B<-i> Prompt for confirmation whenever the copy would overwrite an existing target.
+
+B<-p> Preserve source file attributes (like modDate) as much as possible onto the target.
+
+B<-v> Verbose. Echo "cp source target" before copy is done.
+
+=cut
+
+run(@ARGV) unless caller;
+
+sub run {
+	my @args = @_;
+
+	require Getopt::Long;
+	my %opts;
+
+	my $ret = Getopt::Long::GetOptionsFromArray(
+		\@args,
+		'f' => \$opts{'f'},
+		'i' => \$opts{'i'},
+		'p' => \$opts{'p'},
+		'v' => \$opts{'v'},
+		);
+	my( $source, $destination ) = @args;
+
+	my @unix_like = qw(darwin freebsd linux);
+	if( $^O eq 'MSWin32' ) {
+		# https://home.csulb.edu/~murdock/copy.html
+		my @command = 'copy';
+		push @command, '/-Y' if $opts{i};
+		push @command, $source, $destination;
+
+		print "cp $source $destination\n" if $opts{v};
+		my $rc = system { $command[0] } @command
+		}
+	elsif( grep { $^O eq $_ } @unix_like and in_path('cp') ) {
+		# Although File::Copy seems like it should do the right thing,
+		# it doesn't.
+		my @command = 'cp';
+		push @command, map { "-$_" } grep { $opts{$_} } qw(i f p v );
+		push @command, $source, $destination;
+
+		my $rc = system { $command[0] } @command
+		}
+	else {
+		require File::Copy;
+		print "cp $source $destination\n" if $opts{v};
+		File::Copy::copy( $source, $destination );
+		}
+	};
+
+sub in_path {
+	my( $command ) = @_;
+	foreach my $dir ( split /$Config{path_sep}/, $ENV{PATH} ) {
+		my $path = catfile( $dir, $command );
+		return 1 if -x $path;
+		}
+	return 0;
+	}
+
+__END__
 
 #######   P R O C E S S   - O P T I O N S   ####################################
 my $VERBOSE = 0;