isfd | isam file identifier |
a pointer to the base file descriptor iserrno field, giving the current error code, as detailed in Error Codes, or NULL on error.
if isfd is NULL - for instance when an isOpen or isBuild call fails - then the current value of the global errno value is returned.
PLEASE NOTE that this call is currently deprecated and will probably be replaced with one that returns the value itself, and not a pointer.