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ASSERT(3)	       FreeBSD Library Functions Manual		     ASSERT(3)

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 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
     abort(3)

STANDARDS
     The assert() macro	conforms to ISO/IEC 9899:1999 (``ISO C99'').

HISTORY
     An	assert macro appeared in Version 6 AT&T	UNIX.

FreeBSD	11.1		       January 26, 1999			  FreeBSD 11.1
NAME | SYNOPSIS | DESCRIPTION | EXAMPLES | SEE ALSO | STANDARDS | HISTORY

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