PC Extra Super CD 1998 January/PCPLUS131.iso/DJGPP/V2/DJLSR201.ZIP/src/libc/ansi/assert/assert.txh

Text File | 1995-07-10 | 874 b | 38 lines

@node assert, misc
@subheading Syntax

@example
#define NDEBUG
#include <assert.h>

assert(expression);
assertval(expression);
@end example

@subheading Description

These macros are used to assist in debugging.  The source code includes
references to assert and assertval, passing them expressions that should
be true (or non-zero).  When the expression equals zero, a diagnostic
message is printed to stderr and the program aborts.

If you define the macro @code{NDEBUG} before including @file{assert.h},
then the macros expand to nothing to reduce code size after debugging is
done.

@subheading Return Value

@code{assert} returns one if it passes, else it aborts.

@code{assertval} returns the value of the expression if nonzero, else it
aborts.

@subheading Example

@example
int strdup(char *s)
@{
  assert(s != 0);
@end example