NAME    [Toc]    [Back]

       pthread_attr_getscope   -  Obtains  the  contention  scope
       attribute of the specified thread attributes object

SYNOPSIS    [Toc]    [Back]

       #include <pthread.h>

       int pthread_attr_getscope(
               const pthread_attr_t *attr,
               int *scope );

LIBRARY    [Toc]    [Back]

       DECthreads POSIX 1003.1c Library (libpthread.so)

STANDARDS    [Toc]    [Back]

       Interfaces documented on this reference  page  conform  to
       industry standards as follows:

       IEEE  Std  1003.1c-1995,  POSIX System Application Program
       Interface

PARAMETERS    [Toc]    [Back]

       Address of the thread attributes object  whose  contention
       scope  attribute  is  obtained.  Receives the value of the
       contention scope attribute of the thread attributes object
       specified by attr.

DESCRIPTION    [Toc]    [Back]

       This  routine  obtains  the  value of the contention scope
       attribute of the thread attributes object specified in the
       attr  argument  and stores it in the location specified by
       the scope argument. The specified attributes  object  must
       already be initialized at the time this routine is called.

       The  contention  scope  attribute  specifies  the  set  of
       threads  with  which  a thread must compete for processing
       resources.  The  contention  scope   attribute   specifies
       whether  the  new thread competes for processing resources
       only with other threads in its own process, called process
       contention  scope,  or  with  all  threads  on the system,
       called system contention scope.

       DECthreads selects at most one thread to execute  on  each
       processor  at  any  point in time. DECthreads resolves the
       contention based on each  thread's  scheduling  attributes
       (for  example,  priority) and scheduling policy (for example,
 round-robin).

       A thread created using a thread  attributes  object  whose
       contention scope attribute is set to PTHREAD_SCOPE_PROCESS
       contends  for  processing  resources  with  other  threads
       within  its  own  process  that  also  were  created  with
       PTHREAD_SCOPE_PROCESS.  It is unspecified how such threads
       are  scheduled  relative  to threads in other processes or
       threads  in  the  same  process  that  were  created  with
       PTHREAD_SCOPE_SYSTEM contention scope.

       A  thread  created  using a thread attributes object whose
       contention scope attribute is set to  PTHREAD_SCOPE_SYSTEM
       contends  for  processing  resources with other threads in
       any process that also were created with PTHREAD_SCOPE_SYSTEM.

NOTES    [Toc]    [Back]

       The  value of the contention scope attribute of a particular
 thread attributes object does not  necessarily  correspond
  to  the  actual  scheduling contention scope of any
       existing thread in your multithreaded program.

RETURN VALUES    [Toc]    [Back]

       If an error condition  occurs,  this  routine  returns  an
       integer  value  indicating  the  type  of  error. Possible
       return values are as follows: Successful completion.   The
       value  specified  by attr is not a valid thread attributes
       object.  This routine is not supported by the  implementation.

ERRORS    [Toc]    [Back]

       None

SEE ALSO    [Toc]    [Back]

       Functions: pthread_attr_init(3), pthread_attr_setscope(3)

       Manuals: Guide to DECthreads and Programmer's Guide



                                         pthread_attr_getscope(3)