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pthread_rwlockattr_setpshared(3c) [sunos man page]

pthread_rwlockattr_getpshared(3C)										 pthread_rwlockattr_getpshared(3C)

NAME
pthread_rwlockattr_getpshared, pthread_rwlockattr_setpshared - get or set process-shared attribute of read-write lock attributes object SYNOPSIS
cc -mt [ flag... ] file... -lpthread [ library... ] #include <pthread.h> int pthread_rwlockattr_getpshared(const pthread_rwlockattr_t *restrict attr, int *restrict pshared); int pthread_rwlockattr_setpshared(pthread_rwlockattr_t *attr, int pshared); The process-shared attribute is set to PTHREAD_PROCESS_SHARED to permit a read-write lock to be operated upon by any thread that has access to the memory where the read-write lock is allocated, even if the read-write lock is allocated in memory that is shared by multiple processes. If the process-shared attribute is PTHREAD_PROCESS_PRIVATE, the read-write lock will only be operated upon by threads created within the same process as the thread that initialised the read-write lock; if threads of differing processes attempt to operate on such a read-write lock, the behaviour is undefined. The default value of the process-shared attribute is PTHREAD_PROCESS_PRIVATE. The pthread_rwlockattr_getpshared() function obtains the value of the process-shared attribute from the initialised attributes object ref- erenced by attr. The pthread_rwlockattr_setpshared() function is used to set the process-shared attribute in an initialised attributes object referenced by attr. If successful, the pthread_rwlockattr_setpshared() function returns 0. Otherwise, an error number is returned to indicate the error. Upon successful completion, the pthread_rwlockattr_getpshared() returns 0 and stores the value of the process-shared attribute of attr into the object referenced by the pshared parameter. Otherwise an error number is returned to indicate the error. The pthread_rwlockattr_getpshared() and pthread_rwlockattr_setpshared() functions will fail if: EINVAL The value specified by attr or pshared is invalid. See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Interface Stability |Standard | +-----------------------------+-----------------------------+ |MT-Level |MT-Safe | +-----------------------------+-----------------------------+ pthread_rwlock_init(3C), pthread_rwlock_rdlock(3C), pthread_rwlock_unlock(3C), pthread_rwlock_wrlock(3C), pthread_rwlockattr_init(3C), attributes(5), standards(5) 23 Mar 2005 pthread_rwlockattr_getpshared(3C)

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pthread_rwlockattr_setpshared(3)			     Library Functions Manual				  pthread_rwlockattr_setpshared(3)

NAME
pthread_rwlockattr_setpshared - Sets the process-shared attribute in a read-write lock attributes object. LIBRARY
DECthreads POSIX 1003.1c Library (libpthread.so) SYNOPSIS
#include <pthread.h> int pthread_rwlockattr_setpshared( pthread_rwlockattr_t *attr, int pshared); PARAMETERS
Address of the read-write lock attributes object whose process-shared attribute is to be set. Value to set in the process-shared attribute of attr. Must be the value PTHREAD_PROCESS_SHARED, to permit access to the read-write lock by any thread in any process that can access the memory where the lock object is allocated, or PTHREAD_PROCESS_PRIVATE, to permit access to the read-write lock only by threads in the same process as the thread that initialized the read-write lock object. DESCRIPTION
This routine uses the value in pshared to set the process-shared attribute in the read-write lock attributes object referenced by attr. The object referenced by attr must be initialized before this routine is called. The value of pshared must be either PTHREAD_PROCESS_SHARED or PTHREAD_PROCESS_PRIVATE, as defined in the pthread.h include file. If the process-shared attribute is set to PTHREAD_PROCESS_PRIVATE, the read-write lock object can only be operated upon by threads created within the same process as the thread that initialized the read-write lock object. If threads of differing processes attempt to operate on such a read-write lock object, the behavior is undefined. The default value of the process-shared attribute of a read-write lock attributes object is PTHREAD_PROCESS_PRIVATE. If the process-shared attribute of a read-write lock attributes object is set to PTHREAD_PROCESS_SHARED, the read-write lock object can be operated upon by any thread that has access to the memory where that object is allocated, even if that object is allocated in memory that is shared by multiple processes. RETURN VALUES
If an error condition occurs, this routine returns an integer value indicating the type of error. Possible return values are as follows: Successful completion. The value specified by attr is not a valid attributes object, or the value pshared is outside the range of legal values for that attribute. ERRORS
None RELATED INFORMATION
Functions: pthread_rwlockattr_getpshared(3), pthread_rwlockattr_init(3) Manuals: Guide to DECthreads and Programmer's Guide delim off pthread_rwlockattr_setpshared(3)

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