Re: fdopendir (BUG?)

[Adhemerval Zanella <adhemerval.zanella@linaro.org>]

On 28/01/2019 17:42, Jorge Almeida wrote:
> On Mon, Jan 28, 2019 at 6:54 PM Adhemerval Zanella
> <adhemerval.zanella@linaro.org> wrote:
>>
>>
>>
>> On 28/01/2019 10:37, Jorge Almeida wrote:
>>> (the problem also occurs with glibc, besides the fact that glibc
>>> requires also _GNU_SOURCE to compile, contradicting  the linux man
>>> page)
>> Because O_PATH is a Linux extension and it guards such definitions
>> with _GNU_SOURCE. And although man-pages is not the canonical glibc
>> documentation, it does states that O_PATH is only defined if
>> _GNU_SOURCE is also defined (man-pages commit
>> 1135dbe188a48d7fa237396ab371ebf74037c1f6 from 2013-02-13).
> 
> My man page for opendir has the date  2017-09-15 ("release  4.16  of
> the  Linux  man-pages  project") It says:
>    Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
> 
>        fdopendir():
>            Since glibc 2.10:
>                _POSIX_C_SOURCE >= 200809L
>            Before glibc 2.10:
>                _GNU_SOURCE
> 
> I have glibc-2.27
> 

This is for *fdopendir* declaration, the *O_PATH* flag is documented by
open.2 and it defines:

---
CONFORMING TO
       open(), creat() SVr4, 4.3BSD, POSIX.1-2001, POSIX.1-2008.

       openat(): POSIX.1-2008.

       The O_DIRECT, O_NOATIME, O_PATH, and O_TMPFILE flags are Linux-specific.  
One must define _GNU_SOURCE to obtain their definitions.
---