trusty (7) stddef.h.7posix.gz

NAME

       stddef.h - standard type definitions

SYNOPSIS

       #include <stddef.h>

DESCRIPTION

       The <stddef.h> header shall define the following macros:

       NULL   Null pointer constant.

       offsetof(type, member-designator)

              Integer  constant  expression  of  type  size_t,  the value of which is the offset in bytes to the
              structure member (member-designator), from the beginning of its structure (type).

       The <stddef.h> header shall define the following types:

       ptrdiff_t
              Signed integer type of the result of subtracting two pointers.

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

       size_t Unsigned integer type of the result of the sizeof operator.

       The  implementation  shall support one or more programming environments in which the widths of ptrdiff_t,
       size_t, and wchar_t are no greater than  the  width  of  type  long.   The  names  of  these  programming
       environments can be obtained using the confstr() function or the getconf utility.

       The following sections are informative.

APPLICATION USAGE

       None.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       <wchar.h>  ,  <sys/types.h>  , the System Interfaces volume of IEEE Std 1003.1-2001, confstr(), the Shell
       and Utilities volume of IEEE Std 1003.1-2001, getconf

COPYRIGHT

       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition,
       Standard  for  Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base
       Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics Engineers,
       Inc  and  The  Open Group. In the event of any discrepancy between this version and the original IEEE and
       The Open Group Standard, the original IEEE and The Open Group  Standard  is  the  referee  document.  The
       original Standard can be obtained online at http://www.opengroup.org/unix/online.html .