-=> Quoting Jonathan de Boyne Pollard to Phil Crown <=-

 JdBP> If this causes problems with code based upon the results obtained,
 JdBP> then your granularity is too fine, and should be coarsened.  For
 JdBP> example, assume that `someFn' above were returning whether a list was
 JdBP> empty or not, that the calling code were

 JdBP> if (someFn())                           // List is empty
 JdBP> delete the_list, the_list = 0 ;     // So destroy the list

 JdBP> and than it was not desired that a non-empty list be destroyed.

 JdBP> In this case, the entire `if' statement should be an atomic
 JdBP> operation, not just the test function, otherwise another thread could
 JdBP> add elements to the list in between the time that the test function
 JdBP> exits its mutex section and the time that the first thread actually
 JdBP> destroys the list. 

Thanks, now I need to learn what an "atomic" operation is?

Phil Crown
pcrown{at}airmail.net
http://web2.airmail.net/pcrown/

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