pthreads/pthread_rwlock_unlock.3

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  27 .Dd August 4, 1998
  28 .Dt PTHREAD_RWLOCK_UNLOCK 3
  29 .Os
  30 .Sh NAME
  31 .Nm pthread_rwlock_unlock
  32 .Nd release a read/write lock
  33 .Sh SYNOPSIS
  34 .In pthread.h
  35 .Ft int
  36 .Fo pthread_rwlock_unlock
  37 .Fa "pthread_rwlock_t *rwlock"
  38 .Fc
  39 .Sh DESCRIPTION
  40 The
  41 .Fn pthread_rwlock_unlock
  42 function is used to release the read/write lock previously obtained by
  43 .Fn pthread_rwlock_rdlock ,
  44 .Fn pthread_rwlock_wrlock ,
  45 .Fn pthread_rwlock_tryrdlock ,
  46 or
  47 .Fn pthread_rwlock_trywrlock .
  48 .Sh RETURN VALUES
  49 If successful, the
  50 .Fn pthread_rwlock_unlock
  51 function will return zero.
  52 Otherwise, an error number will be returned to indicate the error.
  53 .Pp
  54 The results are undefined if
  55 .Fa rwlock
  56 is not held by the calling thread.
  57 .Sh SEE ALSO
  58 .Xr pthread_rwlock_rdlock 3 ,
  59 .Xr pthread_rwlock_wrlock 3
  60 .Sh STANDARDS
  61 The
  62 .Fn pthread_rwlock_unlock
  63 function is expected to conform to
  64 .St -susv2 .
  65 .Sh ERRORS
  66 The
  67 .Fn pthread_rwlock_unlock
  68 function may fail if:
  69 .Bl -tag -width Er
  70 .It Bq Er EINVAL
  71 The value specified by
  72 .Fa rwlock
  73 is invalid.
  74 .It Bq Er EPERM
  75 The current thread does not own the read/write lock.
  76 .El
  77 .Sh HISTORY
  78 The
  79 .Fn pthread_rwlock_unlock
  80 function first appeared in
  81 .Fx 3.0 .