#!/usr/bin/perl

my $DIR, $PREFIX;
my $BIN_MV = "/bin/mv";
usage() unless scalar(@ARGV);
foreach my $arg (@ARGV)
	{
	if (-d $arg && ! $DIR)
		{
		$DIR = $arg;
		}
	else
		{
		$PREFIX = $arg;
		}
	}
$DIR ||= ".";
opendir DIR, $DIR || die $!;
my @files = ();
while (my $file = readdir DIR)
	{
	next if $file =~ /^\./;
	push @files, $file;
	}
closedir DIR;
foreach my $file (@files)
	{
	system($BIN_MV, "$DIR/$file", "$DIR/$PREFIX-$file");
	}
sub usage
	{
	print "$ ./.prefix.pl DIR/ prefix\n";
	}