#!/usr/bin/perl
#

require 'getopts.pl';
use cs::Upd;

if (!length($ENV{TAPE}))	{ $ENV{TAPE}="/dev/tape"; }

$tapedev=$ENV{TAPE};
$blocksize=32768;

($cmd=$0) =~ s:.*/::;
$usage="Usage: $cmd [-v] [-t tapedevice] [-b blocksize]
	-t tapedevice	Device to open (default: $tapedev).
	-b blocksize	Blocksize of reads (default: $blocksize).
	-v		Verbose.
";

$badopts=0;
$verbose=-t 1;
&Getopts('vt:b:') || ($badopts=1);
$tapedev=$opt_t if defined $opt_t;
$blocksize=$opt_b if defined $opt_b;
$verbose=$opt_v if defined $opt_v;

if ($blocksize !~ /^\d+$/ || $blocksize < 1)
{ print STDERR "$cmd: $blocksize: blocksize must be a positive integer\n";
  $badopts=1;
}

if ($#ARGV >= $[)
{ print STDERR "$cmd: extra arguments: @ARGV\n";
  $badopts=1;
}

die $usage if $badopts;

if ($tapedev ne '-')
{ if (!open(STDIN,"< $tapedev\0"))
  { die "$cmd: can't open $tapedev: $!\n";
  }
}

select(STDERR);

$xit=0;

$blocks=0;
$bsize=0;
$hadeof=0;
BLOCK:
while (($n=sysread(STDIN,$_,$blocksize)) >= 0)
{ if ($n != $bsize)
  { if ($blocks > 0)
    { $verbose && out('');
      print STDOUT "$blocks x $bsize\n";
    }

    $blocks=0;
    $bsize=$n;
  }

  if ($n == 0)
  { $verbose && out('');
    print STDOUT "EOF\n";
    last BLOCK if $hadeof;	# EOF,EOF ==> EOM
    $hadeof=1;
  }
  else
  { $blocks++;
    $verbose && out("$blocks x $bsize");
    $hadeof=0;
  }
}

$verbose && out('');
if ($n < 0)
{ print STDERR "$cmd: read($tapedev,$blocksize): $!\n";
  $xit=1;
}

exit $xit;