NAME
assert - abort the program if assertion is false
SYNOPSIS
#include <assert.h>
void assert(scalar expression);
DESCRIPTION
If the macro NDEBUG was defined at the moment <assert.h> was last
included, the macro assert() generates no code, and hence does nothing
at all. Otherwise, the macro assert() prints an error message to
standard error and terminates the program by calling abort(3) if
expression is false (i.e., compares equal to zero).
The purpose of this macro is to help the programmer find bugs in his
program. The message "assertion failed in file foo.c, function
do_bar(), line 1287" is of no help at all to a user.
RETURN VALUE
No value is returned.
CONFORMING TO
POSIX.1-2001, C89, C99. In C89, expression is required to be of type
int and undefined behavior results if it is not, but in C99 it may have
any scalar type.
BUGS
assert() is implemented as a macro; if the expression tested has side-
effects, program behavior will be different depending on whether NDEBUG
is defined. This may create Heisenbugs which go away when debugging is
turned on.
SEE ALSO
abort(3), assert_perror(3), exit(3)
COLOPHON
This page is part of release 3.24 of the Linux man-pages project. A
description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.