prthreadstate.rst (1710B)
1 PRThreadState 2 ============= 3 4 A thread's thread state is either joinable or unjoinable. 5 6 7 Syntax 8 ------ 9 10 .. code:: 11 12 #include <prthread.h> 13 14 typedef enum PRThreadState { 15 PR_JOINABLE_THREAD, 16 PR_UNJOINABLE_THREAD 17 } PRThreadState; 18 19 20 Enumerators 21 ~~~~~~~~~~~ 22 23 ``PR_UNJOINABLE_THREAD`` 24 Thread termination happens implicitly when the thread returns from 25 the root function. The time of release of the resources assigned to 26 the thread cannot be determined in advance. Threads created with a 27 ``PR_UNJOINABLE_THREAD`` state cannot be used as arguments to 28 :ref:`PR_JoinThread`. 29 ``PR_JOINABLE_THREAD`` 30 Joinable thread references remain valid after they have returned from 31 their root function until :ref:`PR_JoinThread` is called. This approach 32 facilitates management of the process' critical resources. 33 34 35 Description 36 ----------- 37 38 A thread is a critical resource and must be managed. 39 40 The lifetime of a thread extends from the time it is created to the time 41 it returns from its root function. What happens when it returns from its 42 root function depends on the thread state passed to :ref:`PR_CreateThread` 43 when the thread was created. 44 45 If a thread is created as a joinable thread, it continues to exist after 46 returning from its root function until another thread joins it. The join 47 process permits strict synchronization of thread termination and 48 therefore promotes effective resource management. 49 50 If a thread is created as an unjoinable (also called detached) thread, 51 it terminates and cleans up after itself after returning from its root 52 function. This results in some ambiguity after the thread's root 53 function has returned and before the thread has finished terminating 54 itself.