🚀 go-pugleaf

ok@goanna.cs.rmit.oz.au (Richard A. O'Keefe) writes:

>Now I wonder:  if I want to allocate an array with elements of known size
>but with number of elements not known until run-time, and if I don't really
>care what the initial contents are, _is_ there something in the standard to
>make
>	p = calloc(NumberOfElements, sizeof *p)
>better than
>	p = malloc(NumberOfElements * sizeof *p) ?

No.  The only required difference is the calling sequence and that
calloc clears the memory to all bits zero.

That said, suppose we have a system where int and size_t are 16 bits,
but it is possible to allocate an object bigger than 64K.  A
careful library implementor would ensure that a call like
	calloc(68, 1000)
did not result in integer overflow inside calloc, but would allocate
68000 bytes.  You couldn't do that with (ordinary) malloc.  (I
actually had to implement this on a pre-Standard system one time.)
I don't think the Standard requires this sort of care, but I would
expect it from a quality implementation.
-- 

Steve Clamage, TauMetric Corp, steve@taumet.com
Vice Chair, ANSI C++ Committee, X3J16