1pthread_mutex_getprioceiliSntga(n3dCa)rd C Library Funpctthiroenasd_mutex_getprioceiling(3C)
2
6 pthread_mutex_getprioceiling, pthread_mutex_setprioceiling - change
7 priority ceiling of a mutex
8
10 cc -mt [ flag... ] file... -lpthread [ library... ]
11 #include <pthread.h>
12 int pthread_mutex_getprioceiling(const pthread_mutex_t *restrict mutex,
14 int *restrict prioceiling);
15 int pthread_mutex_setprioceiling(pthread_mutex_t *restrict mutex,
18 int prioceiling, int *restrict old_ceiling);
19
22 The pthread_mutex_getprioceiling() function returns the current prior‐
23 ity ceiling of the mutex.
24 The pthread_mutex_setprioceiling() function either locks the mutex if
27 it is unlocked, or blocks until it can successfully lock the mutex,
28 then it changes the mutex's priority ceiling and releases the mutex.
29 When the change is successful, the previous value of the priority ceil‐
30 ing is returned in old_ceiling. The process of locking the mutex need
31 not adhere to the priority protect protocol.
32 If the pthread_mutex_setprioceiling() function fails, the mutex prior‐
35 ity ceiling is not changed.
36 The ceiling value should be drawn from the range of priorities for the
39 SCHED_FIFO policy. When a thread acquires such a mutex, the policy of
40 the thread at mutex acquisition should match that from which the ceil‐
41 ing value was derived (SCHED_FIFO, in this case). If a thread
42 changes its scheduling policy while holding a ceiling mutex, the
43 behavior of pthread_mutex_lock() and pthread_mutex_unlock() on this
44 mutex is undefined. See pthread_mutex_lock(3C).
45 The ceiling value should not be treated as a persistent value resident
48 in a pthread_mutex_t that is valid across upgrades of Solaris. The
49 semantics of the actual ceiling value are determined by the existing
50 priority range for the SCHED_FIFO policy, as returned by the
51 sched_get_priority_min() and sched_get_priority_max() functions (see
52 sched_get_priority_min(3C)) when called on the version of Solaris on
53 which the ceiling value is being utilized.
54
56 Upon successful completion, the pthread_mutex_getprioceiling() and
57 pthread_mutex_setprioceiling() functions return 0. Otherwise, an error
58 number is returned to indicate the error.
59
61 The pthread_mutex_getprioceiling() and pthread_mutex_setprioceiling()
62 functions may fail if:
63 EINVAL The value specified by mutex does not refer to a currently
65 existing mutex.
66 The pthread_mutex_setprioceiling() function will fail if:
70 EINVAL The mutex was not initialized with its protocol attribute
72 having the value of PTHREAD_PRIO_PROTECT.
73 EINVAL The priority requested by prioceiling is out of range.
76 EPERM The caller does not have the privilege to perform the opera‐
79 tion.
80
83 See attributes(5) for descriptions of the following attributes:
84 ┌─────────────────────────────┬─────────────────────────────┐
89 │ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
90 ├─────────────────────────────┼─────────────────────────────┤
91 │Interface Stability │Committed │
92 ├─────────────────────────────┼─────────────────────────────┤
93 │MT-Level │MT-Safe │
94 ├─────────────────────────────┼─────────────────────────────┤
95 │Standard │See standards(5). │
96 └─────────────────────────────┴─────────────────────────────┘
97
99 pthread_mutex_init(3C), pthread_mutex_lock(3C), sched_get_prior‐
100 ity_min(3C), attributes(5), standards(5)
101SunOS 5.11 1 Apr 2008 pthread_mutex_getprioceiling(3C)