man/pthread_cond_wait.3

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  31 .Dd February 16, 2006
  32 .Dt PTHREAD_COND_WAIT 3
  33 .Os Darwin
  34 .Sh NAME
  35 .Nm pthread_cond_wait
  36 .Nd wait on a condition variable
  37 .Sh SYNOPSIS
  38 .In pthread.h
  39 .Ft int
  40 .Fn pthread_cond_wait "pthread_cond_t *cond" "pthread_mutex_t *mutex"
  41 .Sh DESCRIPTION
  42 The
  43 .Fn pthread_cond_wait
  44 function atomically blocks the current thread waiting on the condition
  45 variable specified by
  46 .Fa cond ,
  47 and releases the mutex specified by
  48 .Fa mutex .
  49 The waiting thread unblocks only after another thread calls
  50 .Xr pthread_cond_signal 3 ,
  51 or
  52 .Xr pthread_cond_broadcast 3
  53 with the same condition variable, and the current thread reacquires the lock
  54 on
  55 .Fa mutex .
  56 .Sh RETURN VALUES
  57 If successful, the
  58 .Fn pthread_cond_wait
  59 function will return zero.
  60 Otherwise an error number will be returned to
  61 indicate the error.
  62 .Sh ERRORS
  63 The
  64 .Fn pthread_cond_wait
  65 function will fail if:
  66 .Bl -tag -width Er
  67 .It Bq Er EINVAL
  68 The value specified by
  69 .Fa cond
  70 or the value specified by
  71 .Fa mutex
  72 is invalid.
  73 .El
  74 .Sh SEE ALSO
  75 .Xr pthread_cond_broadcast 3 ,
  76 .Xr pthread_cond_destroy 3 ,
  77 .Xr pthread_cond_init 3 ,
  78 .Xr pthread_cond_signal 3 ,
  79 .Xr pthread_cond_timedwait 3
  80 .Sh STANDARDS
  81 The
  82 .Fn pthread_cond_wait
  83 function conforms to
  84 .St -p1003.1-96 .