gzip on PDP-11: not so simple

Peter Chubb peterc at softway.com.au
Wed Mar 25 17:43:00 AEST 1998


>>>>> "Greg" == Greg Lehey <grog at lemis.com> writes:

Greg> OK, I've found the problems with gzip, and they're not
Greg> encouraging.  It would appear that the undefined references are
Greg> undefined because they refer to data which is too large.  Here's
Greg> the preprocessor output:

Greg>   uch inbuf[ 0x8000 + 64 ]; uch outbuf[ 16384 +2048 ]; ush
Greg> d_buf[ 0x8000 ]; uch window[ 2*0x8000 ]; # 194 "gzip.c"

You need to decrease the window size -- try setting it to 8k (instead
of 32k)

There should be a 
#define WSIZE 0x8000
somewhere.

It may be worth playing with a decompress only version -- compression
will take more space than decompression (you need two windows rather
than one, for a start).  inbuf can be smaller, too.  Try 512 bytes to
match the disc record size.

Peter C

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