Subj : Re: deadlock avoidance
To   : comp.programming.threads
From : Dijkstra
Date : Thu Jul 07 2005 05:10 am

Hi Satendra!

> I guess my statement was misinterpreted.  What i meant by atomic here
> is that if we have lets say an integer i with initial value 0 .Thread
> T1 unconditionally modified to 2 (i = 2)  then T2 at any time will read
> it as either 0 or 2 but nothing in between, I agree that with c++
> objects this might not be true. I still don't understand why a function
> who is just checking/reading the value of a global variable can't be
> reentrant ?

Don't get me wrong either, sorry! I understood your statement. ;-) As I
see here, other fellow posters already replied explaining in more
detail why it's wrong.

Robertwess explained it perfectly, on a reply. You can not warrantee
that a simple assignment or check, or read or watherver for that
matter, is atomic on every platform on earth. His example of an 8 bit
platform assignment/check of a 32 bit word is very enlighten.

Cheers,
Jose Miguel.

.