Re: closedir()

[Jorge Almeida <jjalmeida@gmail.com>]

On Fri, Feb 1, 2019 at 12:27 AM Rich Felker <dalias@libc.org> wrote:
>
> On Thu, Jan 31, 2019 at 09:58:06PM +0000, De Paula, Judah wrote:

> > http://man7.org/linux/man-pages/man3/closedir.3.html
>
> Hi,
>
> Passing an invalid pointer to closedir is undefined behavior, and in
> musl the preferred effect for undefined behavior when it's not costly
> to attempt to detect is a quick crash so that the point of error in
> the program can be identified and fixed.
>

Is there a standard that says it is undefined behavior? According to
the man page quoted by the OP, and also according to
http://pubs.opengroup.org/onlinepubs/007904975/functions/closedir.html,
it should return -1 and set errno to EBADF.
Some of us _do_ check return codes. Getting a segfault doesn't seem
more helpful than a message saying which function failed and why. As
an amateur, I'm just trying to figure out what to do when I need to
use a function I'm not very familiar with. Reading the manual seems
pointless. Can you suggest a reliable, accessible source of
information?

Thanks,

Jorge Almeida