#!/usr/bin/perl -w
# keys.pl 1.0.0, 13-jul-2005
# petar marinov, http:/geocities.com/h2428, this is public domain

use strict;
$| = 1;
my $got = '';
while (1) {
  # wait for a sequence to begin
  $got = getone() while (ord($got) == 0);
  # process a sequence ($got already holds the first character)
  while (ord($got) != 0) {
    exit(0) if ($got eq 'x');
    printf("\\x%02x", ord($got));
    $got = getone();
  }
  print "\n";
}
exit(0);


 BEGIN {
   use POSIX qw(:termios_h);
   use Fcntl;
 
   my ($term, $oterm, $echo, $noecho);
   $term = POSIX::Termios->new();
   $term->getattr(fileno(STDIN));
   $oterm = $term->getlflag();
 
   # puts console in a raw mode -- permits non-blocking reading
   sub raw {
     my $flags = 0;
     $term->setlflag($oterm & ~(ECHO | ECHOK | ICANON));
     $term->setcc(VTIME, 1);
     $term->setattr(fileno(STDIN), TCSANOW);
     fcntl(STDIN, F_GETFL, $flags)
       or die "Couldn't get flags for HANDLE : $!\n";
     $flags |= O_NONBLOCK;
     fcntl(STDIN, F_SETFL, $flags)
       or die "Couldn't set flags for HANDLE: $!\n";
   }
 
   # restores console to original mode
   sub cooked {
     print "restore console mode\n";
     $term->setlflag($oterm);
     $term->setcc(VTIME, 0);
     $term->setattr(fileno(STDIN), TCSANOW);
   }
 
   # reads character or times out
   sub getone {
     my $key = ' ';
     my ($rv, $rin, $win, $ein);
     my ($nfound, $timeleft, $rout, $wout, $eout);
 
     $rin = $win = $ein = '';
     vec($rin, fileno(STDIN), 1) = 1;
     $ein = $rin | $win;
     ($nfound,$timeleft) =
       select($rout=$rin, $wout=$win, $eout=$ein, 0.10);
     return chr(0) if $nfound == 0;
     $rv = sysread(STDIN, $key, 1);
     return chr(0) if (!defined($rv));
     return $key;
   }
 
   raw();
   print "press 'x' to exit\n";
 }
 
 END {
   cooked() 
 }