Subj : Re: Diff between concurrent and asynchronous programming
To   : comp.programming.threads
From : David Schwartz
Date : Mon Jul 11 2005 09:31 pm


"invincible" <mohan.bhakri@in.bosch.com> wrote in message 
news:davcj9$ggv$1@ns2.fe.internet.bosch.com...

> Hi All, I wanted to know difference between concurrent and asynchronous
> programming in lay-mans language.

    In layman's language, the two terms are often used to mean the same 
thing. But if people are being precise, the difference is this:

    In concurrent programming, you write code such that more than one piece 
of it will run at the same time. That is, you may have two functions, A and 
B, and they may be running at the same time. That is, the computer may be on 
line 10 of A and line 11 of B at the same time, and then move on to line 11 
of A and line 12 of B.

    In asynchonous programming, you write code such that you start an 
operation and the operation continues without further intervention on your 
part. For example, you may ask the disk to read some part of a file, and 
then your program goes on and does other things while the disk reads the 
file. Later on, you either check to see if the read has completed or rig 
things so that something else tells you when the operation has completed.

    They both have the effect of allowing your program to get more than one 
thing done at a time, but they accomplish this in different ways.

    DS

.