#!/usr/local/bin/perl -w
# $Header$

#
# Usage:
#	select.patch patch.name <file.adat >file.patch.adat
#
# This filter prints that part of standard input starting with a
# line of the form (eg)
#	## +z patch
# and continuing up to and including two consecutive newlines.
#

use strict;

if (scalar(@ARGV) != 1)
	{ die "usage: select.patch patch.name <data >data-for-that-patch\n"; }
my $patch_name = $ARGV[0];

my $in_selected_patch = 0;
my $newline_count = 0;
	while (my $line = <STDIN>)
	{
	if ($line =~ /^### \Q${patch_name}/o)
		{ $in_selected_patch = 1; }
	if ($line =~ /^\n/)
		{ ++$newline_count; }
	   else { $newline_count = 0; }

	if ($in_selected_patch)
		{
		print $line;
		if ($newline_count == 2)
			{ last; }
		}
	}