assert(3C)
NAME
assert − verify program assertion
SYNOPSIS
#include <assert.h>
void assert(int expression);
DESCRIPTION
This macro is useful for putting diagnostics into programs. When it is executed, if expression is false (zero), assert() prints
Assertion failed: expression, file xyz, line nnn
on the standard error output and aborts. In the error message, xyz is the name of the source file and nnn the source line number of the assert() statement. The latter are respectively the values of the preprocessor macros __FILE__ and __LINE__.
Compiling with the preprocessor option −DNDEBUG (see cc(1B)), or with the preprocessor control statement #define NDEBUG ahead of the #include <assert.h> statement, will stop assertions from being compiled into the program.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
| MT-Level | Safe |
SEE ALSO
cc(1B), abort(3C), gettext(3C), setlocale(3C), attributes(5)
NOTES
If the application is linked with −lintl, then messages printed from this function are in the native language specified by the LC_MESSAGES locale category; see setlocale(3C).
Since assert() is implemented as a macro, the expression may not contain any string literals.
SunOS 5.6 — Last change: 29 Dec 1996