minow@decvax.UUCP (Martin Minow) (09/23/85)
NULL is a value defined by #include <stdio.h> which is used by the standard I/O package to return error values. It has no other function (if you intend your programs to be portable). Several other library routines, such as malloc() "return a null pointer (0)" to signal errors. (See malloc (3) in the 4.1 bsd handbook.) If you want your programs to be portable, you should create suitably type-casted null pointers as needed: #define NULLST ((char *) 0) #define NULL_FOO ((FOO *) 0) Martin Minow decvax!minow