VMS Help POSIX Threads, TIS routines, tis_read_unlock  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    Unlocks a read-write lock that was acquired for read access.

1 - C Binding

    #include <tis.h>

    int
    tis_read_unlock (
             tis_rwlock_t   *lock);

2 - Arguments

 lock

    Address of the read-write lock to be unlocked.

3 - Description

    This routine unlocks a read-write lock that was acquired for
    read access. If there are no other holders of the lock for read
    access and another thread is waiting to acquire the lock for
    write access, that lock acquisition is granted.

4 - Return Values

    If an error condition occurs, this routine returns an integer
    value indicating the type of error. Possible return values are as
    follows:

    Return      Description

    0           Successful completion.
    [EINVAL]    The value specified by lock is not a valid read-write
                lock.

5 - Associated Routines

       tis_read_lock()
       tis_read_trylock()
       tis_rwlock_destroy()
       tis_rwlock_init()
       tis_write_lock()
       tis_write_trylock()
       tis_write_unlock()