#!/usr/bin/perl

# Convert files with 4 bytes per doubleword to 3 bytes
# per doubleword.

foreach $f (@ARGV) {
  if (-f "$f.od") {
    warn "Skipping $f.od: exists\n";
    next;
  }
  open(INPUT, $f) || die "$f: $!";
  binmode(INPUT);
  open(OUTPUT, ">$f.od") || "$f.od: $!";
  warn "Writing $f.od\n";
  while (read(INPUT, $buf, 4)) {
    @b = unpack("CCCC", $buf);
    printf OUTPUT "%04o\n%04o\n%04o\n", $b[0], $b[2], $b[1]<<4|$b[3];
  }
  close(INPUT) || die "$f: $!";
  close(OUTPUT) || die "$f.od: $!";
}
exit 0;