VMS Help POSIX Threads, PTHREAD routines, pthread_key_setname_np, Arguments  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 key

    Address of the thread-specific data key object whose object name
    is to be changed.

 name

    Object name value to copy into the key object.

 mbz

    Reserved for future use. The value must be zero (0).