bionic (3) pthread_mutexattr_setpshared.3.gz

Provided by: manpages-dev_4.15-1_all bug

NAME
       pthread_mutexattr_getpshared, pthread_mutexattr_setpshared - get/set process-shared mutex attribute


SYNOPSIS
       #include <pthread.h>

       int pthread_mutexattr_getpshared(const pthread_mutexattr_t *attr,
                                        int *pshared);
       int pthread_mutexattr_setpshared(pthread_mutexattr_t *attr,
                                        int pshared);

       Compile and link with -pthread.


DESCRIPTION
       These  functions  get  and set the process-shared attribute in a mutex attributes object.  This attribute
       must be appropriately set to ensure correct, efficient operation of a mutex created using this attributes
       object.

       The process-shared attribute can have one of the following values:

       PTHREAD_PROCESS_PRIVATE
              Mutexes  created  with  this  attributes  object  are  to be shared only among threads in the same
              process that initialized the mutex.  This is  the  default  value  for  the  process-shared  mutex
              attribute.

       PTHREAD_PROCESS_SHARED
              Mutexes  created with this attributes object can be shared between any threads that have access to
              the memory containing the object, including threads in different processes.

       pthread_mutexattr_getpshared() places the value of the process-shared attribute of the  mutex  attributes
       object referred to by attr in the location pointed to by pshared.

       pthread_mutexattr_setpshared()  sets  the  value  of the process-shared attribute of the mutex attributes
       object referred to by attr to the value specified in pshared.

       If attr does not refer to an initialized mutex attributes object, the behavior is undefined.


RETURN VALUE
       On success, these functions return 0.  On error, they return a positive error number.


ERRORS
       pthread_mutexattr_setpshared() can fail with the following errors:

       EINVAL The value specified in pshared is invalid.

       ENOTSUP
              pshared is PTHREAD_PROCESS_SHARED but the implementation does not support process-shared mutexes.


CONFORMING TO
       POSIX.1-2001, POSIX.1-2008.


SEE ALSO
       pthread_mutexattr_init(3), pthreads(7)


COLOPHON
       This page is part of release 4.15 of the Linux man-pages project.  A description of the project,
       information about reporting bugs, and the latest version of this page, can be found at
       https://www.kernel.org/doc/man-pages/.