Re: Revised futex(2) man page for review

["Michael Kerrisk (man-pages)" <mtk.manpages-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>]

On 04/15/2015 12:28 PM, Torvald Riegel wrote:
> On Tue, 2015-04-14 at 23:40 +0200, Thomas Gleixner wrote:
>> On Sat, 28 Mar 2015, Peter Zijlstra wrote:
>>> On Sat, Mar 28, 2015 at 09:53:21AM +0100, Michael Kerrisk (man-pages) wrote:
>>>> So, please take a look at the page below. At this point,
>>>> I would most especially appreciate help with the FIXMEs.
>>>
>>> For people who cannot read that troff gibberish (me)..
>>
>> Ditto :)
>>  
>>> NOTES
>>>        Glibc does not provide a wrapper for this system call;  call  it  using
>>>        syscall(2).
>>
>> You might mention that pthread_mutex, pthread_condvar interfaces are
>> high level wrappers for the syscall and recommended to be used for
>> normal use cases. IIRC unnamed semaphores are implemented with futexes
>> as well.
> 
> If we add this, I'd rephrase it to something like that there are
> high-level programming abstractions such as the pthread_condvar
> interfaces or semaphores that are implemented using the syscall and that
> are typically a better fit for normal use cases.  I'd consider only the
> condvars as something like a wrapper, or targeting a similar use case.

I added this under NOTES:

       Various higher-level programming abstractions are implemented via
       futexes, including POSIX threads mutexes and condition variables,
       as well as POSIX semaphores.

Cheers,

Michael


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