NAME

       assert - insert program diagnostics

SYNOPSIS

       #include <assert.h>

       void assert(scalar expression);

DESCRIPTION

       The  assert()  macro  shall  insert  diagnostics  into programs; it shall expand to a void
       expression. When it is executed, if expression (which shall have a scalar type)  is  false
       (that is, compares equal to 0), assert() shall write information about the particular call
       that failed on stderr and shall call abort().

       The information written about the call that failed shall include the text of the argument,
       the  name  of  the source file, the source file line number, and the name of the enclosing
       function; the latter are, respectively, the values of the  preprocessing  macros  __FILE__
       and __LINE__ and of the identifier __func__.

       Forcing a definition of the name NDEBUG, either from the compiler command line or with the
       preprocessor control statement #define NDEBUG ahead of the #include <assert.h>  statement,
       shall stop assertions from being compiled into the program.

RETURN VALUE

       The assert() macro shall not return a value.

ERRORS

       No errors are defined.

       The following sections are informative.

EXAMPLES

       None.

APPLICATION USAGE

       None.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       abort() , stderr, the Base Definitions volume of IEEE Std 1003.1-2001, <assert.h>

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 .