At Sun, 20 Sep 2020 17:35:52 -0400, John Cowan wrote: Subject: Re: [TUHS] reviving a bit of WWB > > When 0 is coerced implicitly or explicitly to a pointer type, it becomes a > null pointer. That's true even on architectures where all-bits-zero is > *not* a null pointer. However, in contexts where there is no expected > type, as in a call to execl(), the null at the end of the args list has to > be explicitly cast to (char *)0 or some other null pointer. Yeah, that's more to do with the good/bad choice in C to do or not do integer promotion in various situations, and to default parameter types to 'int' unless they are, or are cast to, a wider type (and of course with the rather tricky and almost non-portable way C allows variable length argument lists, along with the somewhat poor way C was cajoled into offering function prototypes to support separate compilation of code units and the exceedingly poor way prototypes deal with variable length argument lists). -- Greg A. Woods Kelowna, BC +1 250 762-7675 RoboHack Planix, Inc. Avoncote Farms