futexes, PI and uclibc

[Matthieu CASTET]

Hi,

Steven Rostedt wrote:
> Hi all,
> 
> I'm writing a chapter in the upcoming revision of Building Embedded Linux
> Systems. In the chapter I talk about futexes and the new Priority
> Inheritance support (robust futexes as well).  This is only supported if
> the libc supports it too. So my question is,
> 
> 1) Does uClibc support futexes
> 2) Does it support PI futexes
> 3) Does it support robust futexes
> 4) if not, will it support it in the future
> 
> We're about to go to print soon, so any information regarding this would
> greatly be appriciated if returned soon.  Otherwise I'll have to just
> leave out a reference to uClibc in this section.
> 
AFAIK, the current version of uClibc 0.9.29, use a old version of 
Linuxthreads that doesn't support futexes.

There is some works to integrate NPTL into uClibc. There is already some 
branches/patch for different architectures, but no uptodate version nor 
version that work with all archs.
This should make uClibc support futexes.
I don't know for PI and robust futexes.

You could grab some info on 
http://thread.gmane.org/gmane.comp.lib.uclibc.general/14204/focus=14229.

Matthieu