Subject: v01i144: chksum, 32-bit file checksumming program
From: [email-masked] (Norman H. Azadian)
Date: 16 Feb 89 18:12:05 GMT
Newsgroups: comp.binaries.ibm.pc

Posting-number: Volume 01 Issue 144
Originally-from: Norman H. Azadian <[email-masked]>
Submitted-by: Norman H. Azadian <[email-masked]>
Archive-name: chksum/chksum.uue

Chksum is a little program that I've developed and used a lot over the
years. The prime difference between it and the ones that it copies, is
that it can read a list of pathnames from stdin.  This turns out to be
very handy indeed. Also, it uses a 32-bit CRC, which means that a false
match is 2**16 times less likely than with the 16-bit brands.  It
produces identical results on both PCs and VAXen.

Performance on an AT-03 with disk caching is just over 1 MByte/minute.
The maximum rate at which I can read the disk, with DOS calls, is about
1.5 MByte/minute.

The 32-bit CRC routine was donated by kind souls on the net.  I have
tweaked it for my use, principally by adding inline optimized assembly
code for my PC. I don't pretend to know what is going on inside, and I
regard it as a minor miracle that it actually produces the same numbers
on PCs as on VAXen.  Perhaps somebody will tell me if it produces the
"right" numbers.

I hereby donate this program to the Public Domain for any and all
purposes. Enjoy.

PAPER:  Norman Azadian; Hasler AG; Belpstrasse 23; 3000 Berne 14; Switzerland
X.400:  [email-masked]
UUCP:   ...{uunet,ukc,mcvax,...}!cernvax!hslrswi!azadian
VOICE:  +41 31 63 2178            BITNET: [email-masked]

[
Will also give byte counts, and total checksum for all files.  Doesn't
take wildcards on command line, but "stuff . | chksum -v --" worked
well for me.

-- R.D.
]