PROLOG

       This  manual  page  is part of the POSIX Programmer's Manual.  The Linux implementation of this interface
       may differ (consult the corresponding Linux manual page for details of Linux behavior), or the  interface
       may not be implemented on Linux.

NAME

       pthread_mutex_consistent — mark state protected by robust mutex as consistent

SYNOPSIS

       #include <pthread.h>

       int pthread_mutex_consistent(pthread_mutex_t *mutex);

DESCRIPTION

       If  mutex is a robust mutex in an inconsistent state, the pthread_mutex_consistent() function can be used
       to mark the state protected by the mutex referenced by mutex as consistent again.

       If an owner of a robust mutex terminates while holding the mutex, the mutex becomes inconsistent and  the
       next thread that acquires the mutex lock shall be notified of the state by the return value [EOWNERDEAD].
       In this case, the mutex does not become normally usable again until the state is marked consistent.

       If  the thread which acquired the mutex lock with the return value [EOWNERDEAD] terminates before calling
       either pthread_mutex_consistent() or pthread_mutex_unlock(), the next thread that acquires the mutex lock
       shall be notified about the state of the mutex by the return value [EOWNERDEAD].

       The behavior is undefined if the value specified by the mutex argument to pthread_mutex_consistent() does
       not refer to an initialized mutex.

RETURN VALUE

       Upon successful completion, the pthread_mutex_consistent() function  shall  return  zero.  Otherwise,  an
       error value shall be returned to indicate the error.

ERRORS

       The pthread_mutex_consistent() function shall fail if:

       EINVAL The mutex object referenced by mutex is not robust or does not protect an inconsistent state.

       These functions shall not return an error code of [EINTR].

       The following sections are informative.

EXAMPLES

       None.

APPLICATION USAGE

       The  pthread_mutex_consistent()  function  is  only responsible for notifying the implementation that the
       state protected by the mutex has been recovered and that normal operations with the mutex can be resumed.
       It is the responsibility of the application to recover the state so it can be reused. If the  application
       is not able to perform the recovery, it can notify the implementation that the situation is unrecoverable
       by  a  call  to  pthread_mutex_unlock() without a prior call to pthread_mutex_consistent(), in which case
       subsequent threads that attempt to lock the  mutex  will  fail  to  acquire  the  lock  and  be  returned
       [ENOTRECOVERABLE].

RATIONALE

       If an implementation detects that the value specified by the mutex argument to pthread_mutex_consistent()
       does  not  refer  to  an initialized mutex, it is recommended that the function should fail and report an
       [EINVAL] error.

FUTURE DIRECTIONS

       None.

SEE ALSO

       pthread_mutex_lock(), pthread_mutexattr_getrobust()

       The Base Definitions volume of POSIX.1‐2017, <pthread.h>

COPYRIGHT

       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1-2017, Standard
       for Information  Technology  --  Portable  Operating  System  Interface  (POSIX),  The  Open  Group  Base
       Specifications  Issue  7, 2018 Edition, Copyright (C) 2018 by the Institute of Electrical and Electronics
       Engineers, Inc and The Open Group.  In the event of any discrepancy between this version and the original
       IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee  document.
       The original Standard can be obtained online at http://www.opengroup.org/unix/online.html .

       Any  typographical  or formatting errors that appear in this page are most likely to have been introduced
       during  the  conversion  of  the  source  files  to  man  page  format.  To  report  such   errors,   see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group                                   2017                      PTHREAD_MUTEX_CONSISTENT(3POSIX)