#!/usr/local/bin/perl
#
$nlines = 5;
$datafile = '/home/hiroshi/vtpwork/data.txt';

if( $ENV{"REQUEST_METHOD"} eq "POST"){
	$n_read =  $ENV{"CONTENT_LENGTH"};
	if( $n_read >= 2000){
		$n_read = 2000;
	}
	$n_read = sysread( STDIN, $txt, $n_read);
}else{
	$txt = $ENV{"QUERY_STRING"};
}
#

open( FH, "+<$datafile");
lock( FH, 2);
seek( FH, 0, 2);
$txt =~ s/[\r\n]//g;
print FH "$txt\n";
close( FH);

open( FH, "$datafile");
@data = <FH>;
close( FH);

$en = $#data;
$st = $en - $nlines + 1;
 
print "Content-type: text/plain\n\n";
print $#data . "\n";
print @data[$st..$en];