NAME    [Toc]    [Back]

     assert - expression verification macro

SYNOPSIS    [Toc]    [Back]

     #include <assert.h>

     assert(expression);

DESCRIPTION    [Toc]    [Back]

     The assert() macro tests the given expression and if  it  is
false, the
     calling  process  is  terminated.   A  diagnostic message is
written to stderr
     and the abort(3) function is called, effectively terminating
the program.

     If expression is true, the assert() macro does nothing.

     The  assert()  macro may be removed at compile time with the
cc(1) option
     -DNDEBUG.

DIAGNOSTICS    [Toc]    [Back]

     The following diagnostic message is  written  to  stderr  if
expression is
     false:

           "assertion
                               "expression", __FILE__, __LINE__);

SEE ALSO    [Toc]    [Back]

     cc(1), abort(3)

STANDARDS    [Toc]    [Back]

     The assert() macro  conforms  to  ANSI  X3.159-1989  (``ANSI
C'').

HISTORY    [Toc]    [Back]

     An assert() macro appeared in Version 6 AT&T UNIX.

OpenBSD      3.6                           June      9,      1993