tis_read_lock(3) [osf1 man page]

tis_read_lock(3)					     Library Functions Manual						  tis_read_lock(3)

NAME

       tis_read_lock - Acquires a read-write lock for read access.

LIBRARY

       Standard C Library (libc.so, libc.a)

SYNOPSIS

       #include <tis.h>

       int   tis_read_lock(
			      tis_rwlock_t   *lock);

STANDARDS

       None

PARAMETERS

       Address of the read-write lock.

DESCRIPTION

       This  routine  acquires	a read-write lock for read access.  This routine waits for any existing lock holder for write access to relinquish
       its lock before granting the lock for read access.  This routine returns when the lock is acquired.  If the lock is already held  for  read
       access, the lock is granted.

       For  each  call to tis_read_lock(3) that successfully acquires the lock for read access, a corresponding call to tis_read_unlock(3) must be
       issued.

       Note that the type tis_rwlock_p is a pointer to type tis_rwlock_t.

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 lock is invalid.

ERRORS

       None

RELATED INFORMATION

       Functions:  tis_read_trylock(3),  tis_read_unlock(3),  tis_rwlock_destroy(3),  tis_rwlock_init(3), tis_write_lock(3), tis_write_trylock(3),
       tis_write_unlock(3)

       Manuals: Guide to DECthreads and Programmer's Guide delim off

																  tis_read_lock(3)

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)