The explain_ustat_or_die function is used to call the
ustat(2) system call. On failure an explanation will be printed to
stderr, obtained from the explain_ustat(3) function, and
then the process terminates by calling exit(EXIT_FAILURE).
The explain_ustat_on_error function is used to call the
ustat(2) system call. On failure an explanation will be printed to
stderr, obtained from the explain_ustat(3) function, but
still returns to the caller.
dev
The dev, exactly as to be passed to the ustat(2) system call.
ubuf
The ubuf, exactly as to be passed to the ustat(2) system call.
RETURN VALUE
The explain_ustat_or_die function only returns on success, see
ustat(2) for more information. On failure, prints an explanation
and exits, it does not return.
The explain_ustat_on_error function always returns the value return
by the wrapped ustat(2) system call.
EXAMPLE
The explain_ustat_or_die function is intended to be used in a
fashion similar to the following example: