assert(3)assert(3)NAMEassert - Inserts program diagnostics
SYNOPSIS
#include <assert.h>
void assert(
int expression );
LIBRARY
Standard C Library (libc)
STANDARDS
Interfaces documented on this reference page conform to industry stan‐
dards as follows:
assert(): XPG4, XPG4-UNIX
Refer to the standards(5) reference page for more information about
industry standards and associated tags.
PARAMETERS
Specifies an expression that is evaluated as TRUE or FALSE. This
expression is evaluated in the same manner as a C language if control
statement.
DESCRIPTION
The assert() macro inserts diagnostics into programs. On execution,
when the expression parameter is false (returns FALSE), this macro
writes information about the particular call that failed, including the
text of the argument, the name of the source file, and the source-file
line number (the latter two are respectively the values of preprocess‐
ing macros __FILE__ and __LINE__) on stderr. The error message is taken
from the standard C library message catalog. The assert() macro then
calls the abort() function to (normally) terminate the process.
When you compile a program with the -DNDEBUG preprocessor option, or
with the #define NDEBUG preprocessor control statement before the
#include <assert.h> statement, calls to the assert() macro have no
effect.
RETURN VALUES
The assert() function returns no value.
SEE ALSO
Routines: abort(3)
Standards: standards(5)assert(3)