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HP-UX Reference > Ppthread_mutexattr_init(3T)Pthread LibraryHP-UX 11i Version 3: February 2007 |
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NAMEpthread_mutexattr_init(), pthread_mutexattr_destroy() — initialize or destroy a mutex attributes object SYNOPSIS#include <pthread.h> int pthread_mutexattr_init( pthread_mutexattr_t *attr ); int pthread_mutexattr_destroy( pthread_mutexattr_t *attr ); DESCRIPTIONpthread_mutexattr_init() initializes the mutex attributes object attr with the default values for all attributes. The attributes object describes a mutex in detail and is passed to the mutex initialization function. When a mutex attributes object is used to initialize a mutex, the values of the individual attributes determine the characteristics of the new mutex. Attributes objects act like additional parameters to object initialization. A single attributes object can be used in multiple calls to the function pthread_mutex_init(). When a mutex is initialized with an attributes object, the attributes are, in effect, copied into the mutex. Consequently, any change to the attributes object will not affect any previously initialized mutexes. Once all mutexes needing a specific attributes object have been initialized, the attributes object is no longer needed. The mutex attributes and their default values are:
If an initialized mutex attributes object is reinitialized, undefined behavior results. pthread_mutexattr_destroy() destroys the mutex attributes object attr. The destroyed mutex attributes object ceases to exist and its resources are reclaimed. Using attr after it has been destroyed results in undefined behavior. A destroyed mutex attributes object can be reinitialized using the pthread_mutexattr_init() function. Mutexes that have been already initialized using this attributes object are not affected by the destruction of the mutex attributes object. RETURN VALUEUpon successful completion, pthread_mutexattr_init() and pthread_mutexattr_destroy() return zero. Otherwise, an error number is returned to indicate the error (the errno variable is not set). ERRORSFor each of the following conditions, if the condition is detected, the pthread_mutexattr_init() and pthread_mutexattr_destroy() functions return the corresponding error number:
AUTHORpthread_mutexattr_init() and pthread_mutexattr_destroy() were derived from the IEEE POSIX P1003.1c standard. SEE ALSOpthread_create(3T), pthread_mutexattr_getpshared(3T), pthread_mutexattr_setpshared(3T), pthread_mutexattr_gettype(3T), pthread_mutexattr_settype(3T), pthread_mutex_init(3T). |
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