This manual page is part of the POSIX Programmer's Manual. The Linux
implementation of this interface may differ (consult the corresponding Linux
manual page for details of Linux behavior), or the interface may not be
implemented on Linux.
assert.h — verify program assertion
The functionality described on this reference page is aligned with the
ISO C standard. Any conflict between the requirements described here
and the ISO C standard is unintentional. This volume of
POSIX.1‐2008 defers to the ISO C standard.
The <assert.h> header shall define the
assert() macro. It refers to the macro NDEBUG which is not defined in
the header. If NDEBUG is defined as a macro name before the inclusion of
this header, the assert() macro shall be defined simply as:
#define assert(ignore)((void) 0)
Otherwise, the macro behaves as described in assert().
The assert() macro shall be redefined according to the
current state of NDEBUG each time <assert.h> is included.
The assert() macro shall be implemented as a macro, not as
a function. If the macro definition is suppressed in order to access an
actual function, the behavior is undefined.
The following sections are informative.
The System Interfaces volume of POSIX.1‐2008, assert()
Portions of this text are reprinted and reproduced in electronic form from IEEE
Std 1003.1, 2013 Edition, Standard for Information Technology -- Portable
Operating System Interface (POSIX), The Open Group Base Specifications Issue
7, Copyright (C) 2013 by the Institute of Electrical and Electronics
Engineers, Inc and The Open Group. (This is POSIX.1-2008 with the 2013
Technical Corrigendum 1 applied.) 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.unix.org/online.html .
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