Where is the man page of syscall _umtx_op?

[Yue Chen]

I need to do some work in the syscall level for _umtx_op. However, I cannot find a man page or other materials about this system call. It is about the userspace pthread locking.

Any idea about where can I find any documentation?

 

[Nojja]

There's no man page for _umtx_op,
but here's the source : http://fxr.watson.org/fxr/source/kern/kern_umtx.c?v=FREEBSD60#L720
Hope it helps.