NAME
assert
—
expression verification
macro
SYNOPSIS
#include
<assert.h>
assert
(expression);
DESCRIPTION
The
assert
()
macro tests the given expression and if it is false,
the calling process is terminated. A diagnostic message is written to
stderr
and the abort(3) function is called, effectively terminating the
program.
If expression is true, the
assert
()
macro does nothing.
The
assert
()
macro may be removed at compile time with the cc(1) option -DNDEBUG
.
DIAGNOSTICS
The following diagnostic message is written to
stderr
if expression is
false:
"assertion \"%s\" failed: file \"%s\", line %d\n", \ "expression", __FILE__, __LINE__);
SEE ALSO
STANDARDS
The assert
() macro conforms to
ANSI X3.159-1989
(“ANSI C89”).
HISTORY
An assert
() macro first appeared in
Version 7 AT&T UNIX.