Re: Friendly amendment #2c [Re: Straw poll on "synchronous" definitions]

Anne Thomas Manes wrote:

> The biggest issue I have with Ugo's definition (and all the others) is that
> they tie synchrony with blocking versus non-blocking. Synchronous means "at
> the same time". Asynchronous means "not at the same time". Whether or not
> the sender has to wait idly for a response is a separate issue.


"At the same time" is only one definition of synchronous. If we're going to
play the dictionary game, dictionary.com yields (inter alia):

   synchronous
   <operating system, communications> 1. Two or more processes
   that depend upon the occurrences of specific events such as
   common timing signals.

   2. Occurring at the same time or at the same rate or with a
   regular or predictable time relationship or sequence.

   Opposite: asynchronous.

   (1996-04-11)
   Source: The Free On-line Dictionary of Computing, © 1993-2001 Denis Howe

On this basis, an interaction pattern in which (e.g.) A sends a request to B and
B sends a reply to A every day at 12:01 UTC for a year is synchronous.
That sounds reasonable to me.....

Personally I don't mind defining one of {synchronous, asynchronous}
as the opposite of the other, as long as the definition involved
is crisp enough that "opposite" is unambiguous. It's a perfectly
respectable way of dealing with the "excluded middle" problem.