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