posix_fallocate(2) && posix_fadvise(2) are somewhat broken

[Maxim Sobolev]

Then it's documentation bug or maybe some discrepancy between SUS and
POSIX.

$ man posix_fadvise
RETURN VALUES
     The posix_fadvise() function returns the value 0 if successful;
otherwise
     the value -1 is returned and the global variable errno is set to
indicate
     the error.
STANDARDS
     The posix_fadvise() interface conforms to IEEE Std 1003.1-2001
     (``POSIX.1'').

HISTORY
     The posix_fadvise() system call first appeared in FreeBSD 9.1.


On Tue, Dec 8, 2015 at 9:01 AM, Garrett Wollman <
wollman at hergotha.csail.mit.edu> wrote:

> In article <CAH7qZfvV-RepAc6N0UxFi2RBthxrd+qHD-Qh5dc-9v=
> NFGCy_w at mail.gmail.com>
> sobomax at freebsd.org writes:
>
> >Hi, while working on some unrelated feature I've noticed that at least
> >those two system calls are not returning proper value (-1) on error.
> >Instead actual errno value is returned from the syscall verbatim,
>
> That is what the specification requires.
>
> RETURN VALUE
>             Upon successful completion, posix_fadvise( ) shall return
>             zero; otherwise, an error number shall be returned to
>             indicate the error.
>
> (Quote from SUSv7 p. 1410, lines 46221-46223.)
>
> -GAWollman
>
>