Multithreaded Programming Guide

Process Scope (Unbound Threads)

PTHREAD_SCOPE_PROCESS threads are created as unbound threads. The association of these threads with LWPs is managed by the threads library.

In most cases, threads should be PTHREAD_SCOPE_PROCESS. These threads have no restriction to execute on a particular LWP, and are equivalent to Solaris thread created without the THR_BOUND flag. The threads library decides the association between individual threads and LWPs.