Q:

How are pthreads implemented in Linux kernel(>2.6) using NPTL? 

I have come across the POSIX-compliant NPTL(native posix thread library) been mentioned at several forums. 
I want to understand how pthreads are implemented with the support of the kernel(linux). 
Can anyone please provide a reference to a good material that explains the design and implementation of pthreads in linux ? 
Thanks

A:

Look at this paper of design and implementation of NPTL by Ulrich Drepper and Ingo Molnar
http://www.akkadia.org/drepper/nptl-design.pdf
I believe a lot had been changed since 2005 and it's not should be used as a reference to point out limitations and shortcomings (that said in header), though it's a great doc about overall design.