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assert(3C)							    assert(3C)

       assert -	verify program assertion

       #include	<assert.h>

       void assert(int expression);

       The  assert()  macro  inserts  diagnostics into applications. When exe-
       cuted, if expression is FALSE (zero), assert() prints the error message

       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 as-
       sert() statement. These are respectively	the values of the preprocessor
       macros __FILE__ and __LINE__.

       Since  assert()	is implemented as a macro, the expression may not con-
       tain any	string literals.

       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

       Messages	 printed  from this function are in the	native language	speci-
       fied by the LC_MESSAGES locale category.	See setlocale(3C).

       See attributes(5) for descriptions of the following attributes:

       |      ATTRIBUTE	TYPE	     |	    ATTRIBUTE VALUE	   |
       |Interface Stability	     |Standard			   |
       |MT-Level		     |Safe			   |

       cc(1B), abort(3C),  gettext(3C),	 setlocale(3C),	 attributes(5),	 stan-

				  30 Mar 2005			    assert(3C)


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