#!/usr/bin/perl

print "Directory path? ";
chop ($_dirpath = <STDIN>);

print "File extension? ";
chop ($_filext = <STDIN>);

print "Replace: ";
chop ($_match = <STDIN>);

print "By: ";
chop ($_newline = <STDIN>);


opendir (DH,$_dirpath) or die "Can't access directory\n";
while ($olditem = $item = readdir DH) 
	{
       if ($item !~ /\.$_filext$/) 
		   {
               print "Skipping $item\n";
               next;
                    }
		$olditem =~ s/\.$_filext$/.bak/;
		rename "$_dirpath/$item","$_dirpath/$olditem";
		open (workinfile,"$_dirpath/$olditem")or die "Can't read Work File\n";
		open (newfile, ">$_dirpath/$item")or die "Can't read new File\n";
		while ($_linein = <workinfile>) 
		   {
		   if ($_linein eq $_match)
                            {
			   printf newfile $_linein, "\n" or die "Can't write File\n";
			   printf newfile $_newline, "\n" or die "Can't write File\n";
                            }
		   else
			   {
			    printf newfile $_linein, "\n" or die "Can't write File\n";
			    }
				next;
		   }
		close (workinfile);
		close (newfile);
	}