assert(3p) — Linux manual page

ASSERT(3P)              POSIX Programmer's Manual             ASSERT(3P)

PROLOG

       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.

NAME

       assert — insert program diagnostics

SYNOPSIS

       #include <assert.h>

       void assert(scalar expression);

DESCRIPTION

       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.1‐2017 defers to the ISO C standard.

       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(3p), stdin(3p)

       The Base Definitions volume of POSIX.1‐2017, assert.h(0p)

COPYRIGHT

       Portions of this text are reprinted and reproduced in electronic
       form from IEEE Std 1003.1-2017, Standard for Information
       Technology -- Portable Operating System Interface (POSIX), The
       Open Group Base Specifications Issue 7, 2018 Edition, Copyright
       (C) 2018 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 .

       Any typographical or formatting errors that appear in this page
       are most likely to have been introduced during the conversion of
       the source files to man page format. To report such errors, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group               2017                        ASSERT(3P)

Pages that refer to this page: assert.h(0p)

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