package Apache::Foo::Filter; use strict; use warnings FATAL => 'all'; sub handler { my $r = shift; $r->log->debug("Filtering response"); $r->send_http_header(); $r = $r->filter_register; my $fh = $r->filter_input; while (<$fh>) { $r->log->debug("Filtering data $_"); # remove the underscores s/_//g; $r->log->debug("Filtered data $_"); print; } } 1;