rewriteto.pl

#!/usr/bin/env perl

# in .qmail:
# | rewriteto something@somewhere.else | forward something@somewhere.else

use warnings;
use strict;

sub munge_to_header {
	my ($new_to) = @_;
	my $read_all_headers = 0;

	while (my $line = <STDIN>) {
		$read_all_headers++ if $line =~ /^$/;
		if (defined $new_to && ! $read_all_headers) {
			print STDERR "rewriteto: replaced '$2' with '$new_to'\n"
				if $line =~ s/^([Tt]o:\s+)(.+)$/$1$new_to/;
		}
		print $line;
	}
}

sub main { my @args = @_;
	munge_to_header($args[0]);
}

exit(main(@ARGV));