Standard C Library Functions              pthreadcondsignal(3C)



NAME
     pthreadcondsignal,  pthreadcondbroadcast  -  signal   or
     broadcast a condition

SYNOPSIS
     cc -mt [ flag... ] file... -lpthread [ library... ]
     #include 

     int pthreadcondsignal(pthreadcondt *cond);


     int pthreadcondbroadcast(pthreadcondt *cond);


DESCRIPTION
     These two functions are used to unblock threads blocked on a
     condition variable.


     The pthreadcondsignal() call unblocks at least one of  the
     threads that are blocked on the specified condition variable
     cond (if any threads are blocked on cond).


     The  pthreadcondbroadcast()  call  unblocks  all   threads
     currently blocked on the specified condition variable cond.


     If more than one thread is blocked on a condition  variable,
     the  scheduling policy determines the order in which threads
     are unblocked. When each thread unblocked as a result  of  a
     pthreadcondsignal()  or  pthreadcondbroadcast()  returns
     from     its     call     to     pthreadcondwait()      or
     pthreadcondtimedwait(),  the  thread  owns  the mutex with
     which      it      called       pthreadcondwait()       or
     pthreadcondtimedwait().  The  thread(s) that are unblocked
     contend for the mutex according to the scheduling policy (if
     applicable), and as if each had called pthreadmutexlock().


     The pthreadcondsignal() or pthreadcondbroadcast()  func-
     tions  may be called by a thread whether or not it currently
     owns the mutex that threads calling  pthreadcondwait()  or
     pthreadcondtimedwait()  have associated with the condition
     variable  during  their  waits;  however,   if   predictable
     scheduling  behavior  is required, then that mutex is locked
     by   the    thread    calling    pthreadcondsignal()    or
     pthreadcondbroadcast().


     The pthreadcondsignal() and pthreadcondbroadcast() func-
     tions  have  no  effect  if  there  are no threads currently



SunOS 5.11          Last change: 23 Mar 2005                    1






Standard C Library Functions              pthreadcondsignal(3C)



     blocked on cond.

RETURN VALUES
     If     successful,     the     pthreadcondsignal()     and
     pthreadcondbroadcast()  functions return  0. Otherwise, an
     error number is returned to indicate the error.

ERORS
     The   pthreadcondsignal()   and   pthreadcondbroadcast()
     function may fail if:

     EINVAL    The value cond does not refer  to  an  initialized
               condition variable.


ATRIBUTES
     See attributes(5) for descriptions of the  following  attri-
     butes:



     
           ATRIBUTE TYPE               ATRIBUTE VALUE       
    
     Interface Stability          Standard                    
    
     MT-Level                     MT-Safe                     
    


SEE ALSO
     pthreadcondinit(3C),                pthreadcondwait(3C),
     pthreadcondtimedwait(3C),   attributes(5),   condition(5),
     standards(5)





















SunOS 5.11          Last change: 23 Mar 2005                    2