Section (3) assert
assert — abort the program if assertion is false
This macro can help programmers find bugs in their programs, or handle exceptional cases via a crash that will produce limited debugging output.
false (i.e., compares equal to zero),
assert() prints an error message to
standard error and terminates the program by calling
abort(3). The error message
includes the name of the file and function containing the
assert() call, the source code
line number of the call, and the text of the argument;
prog: some_file.c:16: some_func: Assertion `val == 0_zsingle_quotesz_ failed.
If the macro
defined at the moment
was last included, the macro
assert() generates no code, and hence does
nothing at all. It is not recommended to define
NDEBUG if using
assert() to detect error conditions since
the software may behave non-deterministically.
For an explanation of the terms used in this section, see attributes(7).
POSIX.1-2001, POSIX.1-2008, 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
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.
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Copyright (c) 1993 by Thomas Koenig (ig25rz.uni-karlsruhe.de)
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Modified Sat Jul 24 21:42:42 1993 by Rik Faith <faithcs.unc.edu>
Modified Tue Oct 22 23:44:11 1996 by Eric S. Raymond <esrthyrsus.com>
Modified Thu Jun 2 23:44:11 2016 by Nikos Mavrogiannopoulos <nmavredhat.com>