Index for Section 3

Alphabetical listing for P

Bottom of page

pthread_mutexattr_setpshared(3)
NAME
  pthread_mutexattr_setpshared - Sets the process-shared attribute of a mutex
  attributes object.

LIBRARY
  DECthreads POSIX 1003.1c Library (libpthread.so)

SYNOPSIS
  #include <pthread.h>

  int	pthread_mutexattr_setpshared(
			pthread_mutexattr_t	  *attr,
			int			  pshared);

PARAMETERS
  attr	    Address of the mutex attributes object whose process-shared
	    attribute is to be set.

  pshared   Value to set in the process-shared attribute of attr. Must be the
	    value PTHREAD_PROCESS_SHARED, to permit access to the mutex in by
	    any thread in any process that can access the memory where the
	    mutex object is allocated, or PTHREAD_PROCESS_PRIVATE, to permit
	    access to the mutex only by threads in the same process as the
	    thread that initialized the mutex object.

DESCRIPTION
  This routine uses the value in pshared to set the process-shared attribute
  in the mutex attributes object referenced by attr. The object referenced by
  attr must be initialized before this routine is called. The value of
  pshared must be either PTHREAD_PROCESS_SHARED or PTHREAD_PROCESS_PRIVATE,
  as defined in the pthread.h include file.

  Setting the process-shared attribute to  PTHREAD_PROCESS_PRIVATE permits a
  mutex to be operated upon by threads created within the same process as the
  thread that initialized the mutex.  If threads of differing processes
  attempt to operate on such a mutex, the behavior is undefined.

  The default value of the process-shared attribute of a mutex attributes
  object is PTHREAD_PROCESS_PRIVATE.

  Setting the process-shared attribute to PTHREAD_PROCESS_SHARED permits a
  mutex to be operated upon by any thread that has access to the memory where
  the mutex is allocated, even if the mutex is allocated in memory that is
  shared by multiple processes.




RETURN VALUES
  If an error condition occurs, this routine returns an integer value
  indicating the type of error.	 Possible return values are as follows:

  0	    Successful completion.

  [EINVAL]  The value specified by attr is not a valid mutex attributes
	    object, or the new value specified for the attribute is outside
	    the range of legal values for that attribute.

ERRORS
  None

RELATED INFORMATION
  Functions: pthread_mutexattr_getpshared(3), pthread_mutexattr_init(3)

  Manuals: Guide to DECthreads and Programmer's Guide

Index for Section 3

Alphabetical listing for P

Top of page