Standard C Library Functions               pthreadmutexinit(3C)



NAME
     pthreadmutexinit, pthreadmutexdestroy  -  initialize  or
     destroy a mutex

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

     int pthreadmutexinit(pthreadmutext *restrict mutex,
          const pthreadmutexattrt *restrict attr);


     int pthreadmutexdestroy(pthreadmutext *mutex);


     pthreadmutext mutex= PTHREADMUTEXINITIALIZER;


DESCRIPTION
     The  pthreadmutexinit()  function  initializes  the  mutex
     referenced  by  mutex  with attributes specified by attr. If
     attr is  NUL, the default mutex attributes  are  used;  the
     effect is the same as passing the address of a default mutex
     attributes object. Upon successful initialization, the state
     of the mutex becomes initialized and unlocked.


     Except for  robust  mutexes,  attempting  to  initialize  an
     already initialized mutex results in undefined behavior.


     The  pthreadmutexdestroy()  function  destroys  the  mutex
     object  referenced  by  mutex;  the mutex object becomes, in
     effect, uninitialized. A destroyed mutex object can  be  re-
     initialized  using pthreadmutexinit(); the results of oth-
     erwise referencing the object after it  has  been  destroyed
     are undefined.


     It is safe to destroy an initialized mutex that is unlocked.
     Attempting  to  destroy  a locked mutex results in undefined
     behavior.


     In cases where default mutex attributes are appropriate, the
     macro  PTHREADMUTEXINITIALIZER  can  be used to initialize
     mutexes  that  are  statically  allocated.  The  effect   is
     equivalent   to   dynamic   initialization   by  a  call  to
     pthreadmutexinit() with parameter attr specified as  NUL,
     except that no error checks are performed.





SunOS 5.11          Last change: 11 Nov 2008                    1






Standard C Library Functions               pthreadmutexinit(3C)



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

ERORS
     The pthreadmutexinit() function will fail if:

     EAGAIN    The system lacked the necessary  resources  (other
               than memory) to initialize another mutex.


     EBUSY     An attempt was detected to  re-initialize a robust
               mutex  previously  initialized  but  not  yet des-
               troyed. See pthreadmutexattrsetrobust(3C).


     EINVAL    An attempt was detected to re-initialize a  robust
               mutex  previously initialized with a different set
               of                 attributes.                 See
               pthreadmutexattrsetrobust(3C).


     ENOMEM    Insufficient  memory  exists  to  initialize   the
               mutex.


     EPERM     The caller does not have the privilege to  perform
               the operation.



     The pthreadmutexinit() function may fail if:

     EBUSY     An  attempt  was  detected  to  re-initialize  the
               object  referenced  by  mutex,  a mutex previously
               initialized but not yet destroyed.


     EINVAL    The value specified by attr or mutex is invalid.



     The pthreadmutexdestroy() function may fail if:

     EBUSY     An attempt was  detected  to  destroy  the  object
               referenced  by  mutex while it is locked or refer-
               enced  (for  example,  while  being  used   in   a
               pthreadcondwait(3C)                           or
               pthreadcondtimedwait(3C)) by another thread.





SunOS 5.11          Last change: 11 Nov 2008                    2






Standard C Library Functions               pthreadmutexinit(3C)



     EINVAL    The value specified by mutex is invalid.


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



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


SEE ALSO
     pthreadcondwait(3C),               pthreadmutexlock(3C),
     pthreadmutexattrsetprioceiling(3C),
     pthreadmutexattrsetprotocol(3C),
     pthreadmutexattrsetpshared(3C),
     pthreadmutexattrsetrobust(3C),
     pthreadmutexattrsettype(3C),    attributes(5),   mutex(5),
     standards(5)





























SunOS 5.11          Last change: 11 Nov 2008                    3