netbsd man page for stddef

STDDEF(3)						   BSD Library Functions Manual 						 STDDEF(3)

NAME
     stddef -- standard type definitions

SYNOPSIS
     #include <stddef.h>

DESCRIPTION
     The <stddef.h> header defines the following types and macros:

	 1.   ptrdiff_t, a signed integer type of the result of subtracting two pointers;

	 2.   size_t, an unsigned integer type of the result of the sizeof() operator;

	 3.   wchar_t, an integer type whose range of values can represent distinct wide-character codes for all members of the largest character
	      set specified among the supported locales: the null character has the code value 0 and each member of the character set has a code
	      value equal to its value when used as the lone character in an integer character constant;

	 4.   NULL, which expands to an implementation-defined null pointer constant; and

	 5.   offsetof(), a macro that expands to an integer constant as described in offsetof(3).

     Some of the described types and macros may appear also in other headers.

SEE ALSO
     offsetof(3), stdlib(3), unistd(3)

STANDARDS
     As described here, the <stddef.h> header conforms to ISO/IEC 9899:1999 (``ISO C99'') and IEEE Std 1003.1-2001 (``POSIX.1'').  Some of the
     types and macros conform to earlier standards such as ANSI X3.159-1989 (``ANSI C89'').

HISTORY
     In the current form the <stddef.h> header was introduced in NetBSD 0.8, the first official release of NetBSD.  Some definitions such as NULL
     were first introduced already in the <nsys/param.h> header of Version 4 AT&T UNIX.

BSD
								  April 10, 2011							       BSD