pthread_rwlockattr_setpshared(3)pthread_rwlockattr_setpshared(3)NAMEpthread_rwlockattr_setpshared - Sets the process-shared attribute in a
read-write lock attributes object
int pshared );
DECthreads POSIX 1003.1c Library (libpthread.so)
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.
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.
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.
Functions: pthread_rwlockattr_getpshared(3), pthread_rwlockattr_init(3)
Manuals: Guide to DECthreads and Programmer's Guide