Just a minor new twist on free()

[Gary Duzan]

In article <4d5780ad.20b6d at apollo.HP.COM> blodgett at apollo.HP.COM (Bruce Blodgett) writes:
=>
=>If you are trying to compile code which may call free() with a NULL
=>argument, and use an implementation of free() that does not handle NULL
=>gracefully, try adding one of the following to <stdlib.h>:
=>
=>#define free(x) ( (x) ? free(x) : ( (void)0 ) )
=>  or
=>#define free(x) { void * ptr = (x); if ( ptr != NULL ) free(ptr); }
=>
=>The former has the side-effect of evaluating the argument to free()
=>twice.  The latter is a statement rather than an expression of type
=>void, and therefore wouldn't work if someone tried to embed a call to
=>free() in an expression (there are not many uses for subexpressions of
=>type void).

   Both will also have the property of recursively expanding free() forever.
Better to call it something else. Your cpp will thank you for it.

                                        Gary Duzan
                                        Time  Lord
                                    Third Regeneration



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