Message-ID: <19980325161754.63486@freebie.lemis.com>
Date: Wed, 25 Mar 1998 16:17:54 +1030
From: Greg Lehey <grog@lemis.com>
To: PDP UNIX Preservation Society <pups@minnie.cs.adfa.oz.au>
Subject: gzip on PDP-11: not so simple
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OK, I've found the problems with gzip, and they're not encouraging.
It would appear that the undefined references are undefined because
they refer to data which is too large.  Here's the preprocessor
output:

  uch  inbuf[   0x8000   + 64     ];
  uch  outbuf[  16384  +2048   ];
  ush  d_buf[  0x8000 ];
  uch  window[ 2*0x8000     ];
# 194 "gzip.c"

      ush  prev[ 1<<(16-1)];
      ush  tab_prefix1[ 1<<(16-1)];

uch and ush are uchar and ushort respectively.  Obviously there's no
way of fitting this into a 64 kB address space.  Possibly there's a
way of shortening the buffers, but it would take more time than I have
right now.  Sorry for raising your hopes.

There are other zip-compatible programs out there, such as unzip.
Maybe somebody should look into them.

Greg