Re: [PATCH] semctl.2: Correct SEM_STAT_ANY description

["Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>]

On 12/30/20 3:33 PM, Manfred Spraul wrote:
> Hi Michael,
> 
> On 12/30/20 2:35 PM, Michael Kerrisk (man-pages) wrote:
>> Hi Manfred,
>>
>> On 12/30/20 12:20 PM, Manfred Spraul wrote:
>>> On 12/30/20 3:03 AM, Yang Xu wrote:
>>>> Hi Manfred
>>>>> Hi,
>>>>>
>>>>>
>>>>> On 12/22/20 12:55 PM, Alejandro Colomar (mailing lists; readonly) wrote:
>>>>>> Hi Yang,
>>>>>>
>>>>>> It looks good to me.
>>>>>> I'll add a few people that might want to comment.
>>>>> The code returns a semid_ds structure, and if I take strace as reference
>>>>> implementation, then user space expects a semid_ds as well.
>>>>> https://github.com/strace/strace/commit/8f0870a780bfd8cd9a91c3b7ad05baccda10bc84
>>>>>
>>>>>
>>>>>
>>>>> In addition, the current page is self-inconsistent: seminfo doesn't
>>>>> contain sem_perm.
>>>> semctl manpage doesn't say seminfo contain sem_perm. Or, I miss something?
>>> The current man page says that SEM_STAT_ANY returns a seminfo structure,
>>> without checking sem_perm.
>>>
>>> This is self-inconsistent: struct seminfo contains global
>>> (per-namespace) information, sem_perm.mode is a per-array information.
>>>
>>> I.e.: It is clear that the man page needs to be updated, and not the code.
>> After reading this thread, I'm not quite clear. Do you mean some
>> additional change is required after Xang Yu's patch?
> 
> Sorry for the confusion:
> 
> No further changes are required.
> 
> (I have crosschecked shmctl, msgctl, actual code, and strace as user 
> space example: After Xang Yu's patch is applied, everything is consistent)

Thanks, Manfred! It's clear to me now.

Cheers,

Michael


-- 
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
Linux/UNIX System Programming Training: http://man7.org/training/