#!/bin/perl -w
use strict;

# this tool outputs the content of the last tag $tag in an xml file
# for the file file.xml:
# <doc><elt>elt 1</elt><elt>elt 2</elt><foo>elt 3</foo></doc>
# last_tag elt file.xml outputs <elt>elt 2</elt> 

my $USAGE= "$0 <tag> [file(s)]";
my $tag= shift || die $USAGE;

my $buffer;          # store the current $tag content
my $add_to_buffer=0; # 0 -> do not add to buffer, 1-> add

open( XML_IN, "pyx @ARGV | ") or die "cannot pyx input file(s): $!";

while( <XML_IN>)
  { if( m/\($tag$/) { $add_to_buffer= 1; $buffer= ''; }  # get start tag
    $buffer.= $_    if( $add_to_buffer);                 # fill buffer
    if( m/\)$tag$/) { $add_to_buffer= 0;              }  # get end tag
  }

close XML_IN;

open( XML_OUT, "| pyxw") or die "cannot output buffer: $!";
print XML_OUT $buffer;
close XML_OUT;

# I need this to output the last line on my linux box with Perl 5.6.1
print "\n";