NAME
assert —
expression verification
macro
SYNOPSIS
#include
<assert.h>
assert(expression);
DESCRIPTION
Theassert()
macro tests the given expression and if it is false, the
calling process is terminated. A diagnostic message is written to
stderr and the function
abort(3) is called, effectively terminating the program.
If expression is true, the
assert()
macro does nothing.
The
assert()
macro may be removed at compile time by defining
NDEBUG as a macro (e.g., by using the
cc(1)
option -DNDEBUG).
EXAMPLES
The assertion:
assert(1 == 0);generates a diagnostic message similar to the following:
Assertion failed: (1 == 0), function
main, file assertion.c, line 100.SEE ALSO
STANDARDS
The assert() macro conforms to
ISO/IEC 9899:1999
(“ISO C99”).
HISTORY
An assert macro appeared in
Version 6 AT&T UNIX.