Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.2 9/18/84; site looking.UUCP
Path: utzoo!watmath!looking!brad
From: brad@looking.UUCP (Brad Templeton)
Newsgroups: net.micro,net.micro.pc,net.lang.c,net.unix-wizards
Subject: Re: Help with C-kermit on SCO Xenix V
Message-ID: <533@looking.UUCP>
Date: Fri, 2-May-86 20:19:29 EDT
Article-I.D.: looking.533
Posted: Fri May  2 20:19:29 1986
Date-Received: Sat, 3-May-86 19:16:13 EDT
References: <294@catnip.UUCP> <329@omen.UUCP>
Reply-To: brad@looking.UUCP (Brad Templeton)
Organization: Looking Glass Software Ltd. Waterloo, Ontario
Lines: 25
Keywords: It isn't working
Xref: watmath net.micro:14493 net.micro.pc:8029 net.lang.c:8804 net.unix-wizards:17904
Summary: 

In article <329@omen.UUCP> caf@omen.UUCP (Chuck Forsberg WA7KGX) writes:
>In article <294@catnip.UUCP> ben@catnip.UUCP (Bennett Broder) writes:
>>I recent obtained a copy of C-kermit 4.2(030) PRERELEASE #2, 5 March 85.
>>We have been using this version at work on a Perkin Elmer 3250XP and an
>>AT&T 3B5, and so I wasn't expecting any problem bringing it up on Xenix.
>>Well the package compiles without error, and appears to work okay, until
>>you attempt to do a transfer.  Then it can't even seem to get past the
>>header packet, and keeps printing SS%S%S%S%S% and the like on the screen.
>>Looking at the debugging output from both ends show that the Xenix machine
>>is computing the checksum incorrectly.  Please, can anyone help???
>>
The problem is indeed a bug in the MSC compiler involving shifts of
signed integers combined with ands.  The fix for kermit is simple enough,
make the int in CHK1 into an "unsigned int"

We're lucky on this one.  It turns out that the Kermit start packet
just happens to have a checksum that triggers this bug.  Even so it took
me several hours to track it down.

I'm going to report it to Microsoft as soon as I see it's not in the new
Beta release I just got.


-- 
Brad Templeton, Looking Glass Software Ltd. - Waterloo, Ontario 519/884-7473