wouldn that make function calls which pass an uncast NULL work?
Not in general. The problem is that there are machines which use different internal representations for pointers to different types of data. The suggested #definition would make uncast NULL arguments to functions expecting pointers to characters to work correctly, but pointer arguments to other types would still be problematical, and legal constructions such as FILE *fp = NULL; could fail. Nevertheless, ANSI C allows the alternate #define NULL ((void *)0) definition for NULL. Besides helping incorrect programs to work (but only on machines with homogeneous pointers, thus questionably valid assistance) this definition may catch programs which use NULL incorrectly (e.g. when the ASCII NUL character was really intended; see question 1.8). 1.6: I use the preprocessor macro #define Nullptr(type) (type *)0 to help me build null pointers of the correct type. A: This trick, though popular in some circles, does not buy much. It is not needed in assignments and comparisons; see question 1.2. It
