Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!swrinde!cs.utexas.edu!sun-barr!apple!altos!gumby!jerry
From: jerry@gumby.Altos.COM (Jerry Gardner)
Newsgroups: comp.dcom.modems
Subject: Ymodem
Message-ID: <4875@gumby.Altos.COM>
Date: 6 May 91 20:42:56 GMT
Reply-To: jerry@altos.Altos.COM (Jerry Gardner)
Organization: Altos Computer Systems, San Jose, CA.
Lines: 22



I'm implementing the Ymodem protocol in my communications program and I'm
puzzled by several things in the specification (from a company called Omen
Technology).

It's not explained in the text, but two of the example Ymodem-batch exchanges
have the receiver NAKing the first EOT from the sender and Acking the second,
followed by the 'C' starting character for the next file.  Why is this 
seemingly convoluted exchange necessary?  Do the examples assume the first
EOT did not arrive successfully?

Is there a better Ymodem specification available?  The Omen Tech. spec. has
holes and ommissions big enough to drive a truck through.  I need something
more rigorous.


-- 
Jerry Gardner, NJ6A					Altos Computer Systems
UUCP: {sun|pyramid|sco|amdahl|uunet}!altos!jerry	2641 Orchard Parkway
Internet: jerry@altos.com				San Jose, CA  95134
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