pthread_mutex_setprioceiling()
Set a mutex's priority ceiling
Synopsis:
#include <pthread.h> int pthread_mutex_setprioceiling( pthread_mutex_t* mutex, int prioceiling, int* old_ceiling );
Arguments:
- mutex
- A pointer to the pthread_mutex_t object that you want to priority ceiling for.
- prioceiling
- The new value for the priority ceiling.
- old_ceiling
- A pointer to a location where the function can store the old value.
Library:
libc
Use the -l c option to qcc to link against this library. This library is usually included automatically.
In order to change the priority ceiling to a value above the maximum permitted for unprivileged processes,
your process must have the PROCMGR_AID_PRIORITY ability enabled.
For more information, see
procmgr_ability()
.
Description:
The pthread_mutex_setprioceiling() function locks mutex (or blocks until it can lock it), changes its priority ceiling to prioceiling, and releases it. When the change is successful, the previous priority ceiling is returned in old_ceiling.
Returns:
- EOK
- Success.
- EINVAL
- The mutex specified by mutex doesn't currently exist, or the priority requested by prioceiling is out of range.
- EPERM
- The calling process doesn't have the required permission; see procmgr_ability() .
Classification:
Safety: | |
---|---|
Cancellation point | No |
Interrupt handler | No |
Signal handler | Yes |
Thread | Yes |