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pmd_lock_upgrade()

Upgrade a shared lock to an exclusive lock on a pmd_attr_t structure

Synopsis:

#include <sys/pm.h>

int pmd_lock_upgrade(pmd_attr_t *pmd);

Arguments:

pmd: Pointer to the pmd_attr_t that's currently locked.

Library:

libpm

Description:

The pmd_lock_upgrade() converts a shared lock to an exclusive lock.

If there are other shared locks currently held, pmd_lock_upgrade() block until those locks are released. Any new attempts to acquire the shared lock is prevented and blocked in pmd_lock_shared().

Returns:

EOK: Success
Error code from pthread_sleepon_lock(), pthread_sleepon_wait(), and pthread_sleepon_unlock().: An error has occurred.

Examples:

For more information, see the device driver chapter.

Classification:

Neutrino

Safety:
Cancellation point	Yes
Interrupt handler	No
Signal handler	Yes
Thread	Yes