assert(3)



NAME

     assert - program verification


SYNOPSIS

     #include <assert.h>

     void assert(int expression)


DESCRIPTION

     Assert is a macro that indicates expression is expected  to  be  true  at
     this  point  in  the  program.   It  causes an abort(3) with a diagnostic
     comment on the standard output when expression is false  (0).   Compiling
     with  the  cc(1)  option  -DNDEBUG  effectively  deletes  assert from the
     program.


DIAGNOSTICS

     `Assertion "expression" failed: file f line n.'  F is the source file and
     n the source line number of the assert statement.