--- /dev/null
+#!/usr/bin/perl
+
+
+open(FILE, $ARGV[2]) || die("Error: cannot open \"$ARGV[2]\" for reading.\n");
+@file = <FILE>;
+close(FILE);
+
+open(FILE, ">$ARGV[2]");
+
+foreach $line (@file)
+{
+ $line =~ s/$ARGV[0]/$ARGV[1]/g;
+
+ print FILE "$line";
+}
+
+close(FILE);