#!/usr/bin/perl -w open(INFILE,$ARGV[0]) or die "INFILE CROAKED"; open(OUTFILE,">$ARGV[1]) or die "OUTFILE CROAKED"; While(){ while(/BEGTITLE.*wirey.*?ENDTITLE/){ $_=~s/wirey/smooth/i; print OUTFILE $_;} } close INFILE; close OUTFILE;