Re: Reentrancy

"Igor Tandetnik" <>
Thu, 9 Apr 2009 11:19:56 -0400
Krat <> wrote:

The wikipedia
article( that
defines "reentrant" gives 6 rules to write reentrant code. According
to the definition a function like this is reentrant :
char reentrant_func (char * ptr)
   return *(ptr + 2);


char * buf = 0;

int main ()
   buf = (char * ) malloc (256);
   strcpy (buf, "Reentrant");

   char c = reentrant_func (buf);

In call-2 we supplied a pointer to a global data so the function call
may not be reentrant.

A function can be reentrant or not. It's meaningless to say that a
particular function call is reentrant or not - you can't make the same
call twice.

In any case, in what sense is the situation you show non-reentrant? Does
the function not successfully return the third character of the
passed-in buffer? Will it not continue to do so even if called

So I think "not only functions but also
function calls should be reentrant".

Define "reentrant function call". I'm not familiar with the term.
With best wishes,
    Igor Tandetnik

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