[TUHS] Non-US Unix Activities

Steve Johnson scj at yaccman.com
Sat Apr 8 08:08:48 AEST 2017

At AT&T, the evolution from B to C was quite smooth, as was the
evolution of C itself.   Most B programs were converted to "nb" (the
first C incarnation) by hacking on the character strings and putting
in some types where needed.   It wasn't a big deal.  So I'd be
surprised if there were substantial B programs that survived.

One lesson learned that I've never forgotten is how smooth it is to
evolve a language using the following process:

	* Announce that the change is coming and explain why
	* Change the compiler to accept both the old and new syntax
	* Produce a simple warning message when the old syntax was used, but
make it still work
	* Produce a more complicated, verbose message, but still make it work
	* Produce a message that says "After date xxxx, the old stuff won't
work any more"
	* On the date, change the warning to fatal, but keep recognizing the
old syntax and emit "Error: You used the old xxx, change to the new
	* Eventually, stop recognizing the old syntax and remove the message.

	Dennis was a master at this strategy, so things like the otherwise
painful evolution of changing =+ to += went well.

----- Original Message -----
From: "Robert Swierczek" <rmswierczek at gmail.com>
To:"Toby Thain" <toby at telegraphics.com.au>
Cc:<tuhs at minnie.tuhs.org>
Sent:Fri, 7 Apr 2017 17:51:03 -0400
Subject:Re: [TUHS] Non-US Unix Activities

 > Yes, there's always SOME way to avoid it, but obviously
significantly more
 > work. Just depends what the priorities are... Preserving fanfold
seems like
 > a strange priority, wouldn't it be more practical bound book-like
 > Or, similar to your suggestion, load it into a compatible printer
(so that
 > it can be sprocket fed), with some kind of takeup spool, then form
 > pages through, snapping each one between feeds.

 Fully agree! If there is anything I can do to help get that online
 (in whatever form) let me know.

 Are there any other surviving examples of B code from that era in
 ballpark of complexity?

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