pthread_mutexattr_getpshared(3)                       Library Functions Manual

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

LIBRARY
       POSIX threads library (libpthread, -lpthread)

SYNOPSIS
       #include <pthread.h>

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

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.

STANDARDS
       POSIX.1-2008.

HISTORY
       POSIX.1-2001.

SEE ALSO
       pthread_mutexattr_init(3), pthreads(7)

Linux man-pages 6.7               2023-10-31   pthread_mutexattr_getpshared(3)