assert

 NAME
  assert  - assert that an expression is true, else abort

 SYNOPSIS
  #include <assert.h>
  assert(condition);                  /* MACRO */

 FUNCTION
  assert checks the condition and if NOT true prints an error
  message indicating the source filename and line number that the
  assert failed at, and then abort()s.

  The DICE version of assert generates a single static string in
  assert.h for each module containing the file name.  Multiple usages
  of assert() refer to the same physical filename string.

 EXAMPLE
  #include <assert.h>

  main(ac, av)
  int ac;
  char **av;
  {
      assert(ac > 1);         /*  expect at least one argument!   */
      return(0);
  }

 INPUTS
  expression      - an expression which the macro converts into
                an if(!(expression)).

 RESULTS
  none