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+Mutex Manager
+#############
+
+Introduction
+============
+
+The mutex manager implements the functionality required of the mutex
+manager as defined by POSIX 1003.1b-1996. This standard requires that
+a compliant operating system provide the facilties to ensure that
+threads can operate with mutual exclusion from one another and
+defines the API that must be provided.
+
+The services provided by the mutex manager are:
+
+- ``pthread_mutexattr_init`` - Initialize a Mutex Attribute Set
+
+- ``pthread_mutexattr_destroy`` - Destroy a Mutex Attribute Set
+
+- ``pthread_mutexattr_setprotocol`` - Set the Blocking Protocol
+
+- ``pthread_mutexattr_getprotocol`` - Get the Blocking Protocol
+
+- ``pthread_mutexattr_setprioceiling`` - Set the Priority Ceiling
+
+- ``pthread_mutexattr_getprioceiling`` - Get the Priority Ceiling
+
+- ``pthread_mutexattr_setpshared`` - Set the Visibility
+
+- ``pthread_mutexattr_getpshared`` - Get the Visibility
+
+- ``pthread_mutex_init`` - Initialize a Mutex
+
+- ``pthread_mutex_destroy`` - Destroy a Mutex
+
+- ``pthread_mutex_lock`` - Lock a Mutex
+
+- ``pthread_mutex_trylock`` - Poll to Lock a Mutex
+
+- ``pthread_mutex_timedlock`` - Lock a Mutex with Timeout
+
+- ``pthread_mutex_unlock`` - Unlock a Mutex
+
+- ``pthread_mutex_setprioceiling`` - Dynamically Set the Priority Ceiling
+
+- ``pthread_mutex_getprioceiling`` - Dynamically Get the Priority Ceiling
+
+Background
+==========
+
+Mutex Attributes
+----------------
+
+Mutex attributes are utilized only at mutex creation time. A mutex
+attribute structure may be initialized and passed as an argument to
+the ``mutex_init`` routine. Note that the priority ceiling of
+a mutex may be set at run-time.
+
+*blocking protcol*
+ is the XXX
+
+*priority ceiling*
+ is the XXX
+
+*pshared*
+ is the XXX
+
+PTHREAD_MUTEX_INITIALIZER
+-------------------------
+
+This is a special value that a variable of type ``pthread_mutex_t``
+may be statically initialized to as shown below:
+.. code:: c
+
+ pthread_mutex_t my_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+This indicates that ``my_mutex`` will be automatically initialized
+by an implicit call to ``pthread_mutex_init`` the first time
+the mutex is used.
+
+Note that the mutex will be initialized with default attributes.
+
+Operations
+==========
+
+There is currently no text in this section.
+
+Services
+========
+
+This section details the mutex manager’s services.
+A subsection is dedicated to each of this manager’s services
+and describes the calling sequence, related constants, usage,
+and status codes.
+
+pthread_mutexattr_init - Initialize a Mutex Attribute Set
+---------------------------------------------------------
+.. index:: pthread_mutexattr_init
+.. index:: initialize a mutex attribute set
+
+**CALLING SEQUENCE:**
+
+.. code:: c
+
+ #include <pthread.h>
+ int pthread_mutexattr_init(
+ pthread_mutexattr_t \*attr
+ );
+
+**STATUS CODES:**
+
+*EINVAL*
+ The attribute pointer argument is invalid.
+
+**DESCRIPTION:**
+
+The ``pthread_mutexattr_init`` routine initializes the mutex attributes
+object specified by ``attr`` with the default value for all of the
+individual attributes.
+
+**NOTES:**
+
+XXX insert list of default attributes here.
+
+pthread_mutexattr_destroy - Destroy a Mutex Attribute Set
+---------------------------------------------------------
+.. index:: pthread_mutexattr_destroy
+.. index:: destroy a mutex attribute set
+
+**CALLING SEQUENCE:**
+
+.. code:: c
+
+ #include <pthread.h>
+ int pthread_mutexattr_destroy(
+ pthread_mutexattr_t \*attr
+ );
+
+**STATUS CODES:**
+
+*EINVAL*
+ The attribute pointer argument is invalid.
+
+*EINVAL*
+ The attribute set is not initialized.
+
+**DESCRIPTION:**
+
+The ``pthread_mutex_attr_destroy`` routine is used to destroy a mutex
+attributes object. The behavior of using an attributes object after
+it is destroyed is implementation dependent.
+
+**NOTES:**
+
+NONE
+
+pthread_mutexattr_setprotocol - Set the Blocking Protocol
+---------------------------------------------------------
+.. index:: pthread_mutexattr_setprotocol
+.. index:: set the blocking protocol
+
+**CALLING SEQUENCE:**
+
+.. code:: c
+
+ #include <pthread.h>
+ int pthread_mutexattr_setprotocol(
+ pthread_mutexattr_t \*attr,
+ int protocol
+ );
+
+**STATUS CODES:**
+
+*EINVAL*
+ The attribute pointer argument is invalid.
+
+*EINVAL*
+ The attribute set is not initialized.
+
+*EINVAL*
+ The protocol argument is invalid.
+
+**DESCRIPTION:**
+
+The ``pthread_mutexattr_setprotocol`` routine is used to set value of the``protocol`` attribute. This attribute controls the order in which
+threads waiting on this mutex will receive it.
+
+The ``protocol`` can be one of the following:
+
+*``PTHREAD_PRIO_NONE``*
+ in which case blocking order is FIFO.
+
+*``PTHREAD_PRIO_INHERIT``*
+ in which case blocking order is priority with the priority inheritance
+ protocol in effect.
+
+*``PTHREAD_PRIO_PROTECT``*
+ in which case blocking order is priority with the priority ceiling
+ protocol in effect.
+
+**NOTES:**
+
+There is currently no way to get simple priority blocking ordering
+with POSIX mutexes even though this could easily by supported by RTEMS.
+
+pthread_mutexattr_getprotocol - Get the Blocking Protocol
+---------------------------------------------------------
+.. index:: pthread_mutexattr_getprotocol
+.. index:: get the blocking protocol
+
+**CALLING SEQUENCE:**
+
+.. code:: c
+
+ #include <pthread.h>
+ int pthread_mutexattr_getprotocol(
+ pthread_mutexattr_t \*attr,
+ int \*protocol
+ );
+
+**STATUS CODES:**
+
+*EINVAL*
+ The attribute pointer argument is invalid.
+
+*EINVAL*
+ The attribute set is not initialized.
+
+*EINVAL*
+ The protocol pointer argument is invalid.
+
+**DESCRIPTION:**
+
+The ``pthread_mutexattr_getprotocol`` routine is used to obtain
+the value of the ``protocol`` attribute. This attribute controls
+the order in which threads waiting on this mutex will receive it.
+
+**NOTES:**
+
+NONE
+
+pthread_mutexattr_setprioceiling - Set the Priority Ceiling
+-----------------------------------------------------------
+.. index:: pthread_mutexattr_setprioceiling
+.. index:: set the priority ceiling
+
+**CALLING SEQUENCE:**
+
+.. code:: c
+
+ #include <pthread.h>
+ int pthread_mutexattr_setprioceiling(
+ pthread_mutexattr_t \*attr,
+ int prioceiling
+ );
+
+**STATUS CODES:**
+
+*EINVAL*
+ The attribute pointer argument is invalid.
+
+*EINVAL*
+ The attribute set is not initialized.
+
+*EINVAL*
+ The prioceiling argument is invalid.
+
+**DESCRIPTION:**
+
+The ``pthread_mutexattr_setprioceiling`` routine is used to set value of the``prioceiling`` attribute. This attribute specifies the priority that
+is the ceiling for threads obtaining this mutex. Any task obtaining this
+mutex may not be of greater priority that the ceiling. If it is of lower
+priority, then its priority will be elevated to ``prioceiling``.
+
+**NOTES:**
+
+NONE
+
+pthread_mutexattr_getprioceiling - Get the Priority Ceiling
+-----------------------------------------------------------
+.. index:: pthread_mutexattr_getprioceiling
+.. index:: get the priority ceiling
+
+**CALLING SEQUENCE:**
+
+.. code:: c
+
+ #include <pthread.h>
+ int pthread_mutexattr_getprioceiling(
+ const pthread_mutexattr_t \*attr,
+ int \*prioceiling
+ );
+
+**STATUS CODES:**
+
+*EINVAL*
+ The attribute pointer argument is invalid.
+
+*EINVAL*
+ The attribute set is not initialized.
+
+*EINVAL*
+ The prioceiling pointer argument is invalid.
+
+**DESCRIPTION:**
+
+The ``pthread_mutexattr_getprioceiling`` routine is used to obtain the
+value of the ``prioceiling`` attribute. This attribute specifies the
+priority ceiling for this mutex.
+
+**NOTES:**
+
+NONE
+
+pthread_mutexattr_setpshared - Set the Visibility
+-------------------------------------------------
+.. index:: pthread_mutexattr_setpshared
+.. index:: set the visibility
+
+**CALLING SEQUENCE:**
+
+.. code:: c
+
+ #include <pthread.h>
+ int pthread_mutexattr_setpshared(
+ pthread_mutexattr_t \*attr,
+ int pshared
+ );
+
+**STATUS CODES:**
+
+*EINVAL*
+ The attribute pointer argument is invalid.
+
+*EINVAL*
+ The attribute set is not initialized.
+
+*EINVAL*
+ The pshared argument is invalid.
+
+**DESCRIPTION:**
+
+**NOTES:**
+
+pthread_mutexattr_getpshared - Get the Visibility
+-------------------------------------------------
+.. index:: pthread_mutexattr_getpshared
+.. index:: get the visibility
+
+**CALLING SEQUENCE:**
+
+.. code:: c
+
+ #include <pthread.h>
+ int pthread_mutexattr_getpshared(
+ const pthread_mutexattr_t \*attr,
+ int \*pshared
+ );
+
+**STATUS CODES:**
+
+*EINVAL*
+ The attribute pointer argument is invalid.
+
+*EINVAL*
+ The attribute set is not initialized.
+
+*EINVAL*
+ The pshared pointer argument is invalid.
+
+**DESCRIPTION:**
+
+**NOTES:**
+
+pthread_mutex_init - Initialize a Mutex
+---------------------------------------
+.. index:: pthread_mutex_init
+.. index:: initialize a mutex
+
+**CALLING SEQUENCE:**
+
+.. code:: c
+
+ #include <pthread.h>
+ int pthread_mutex_init(
+ pthread_mutex_t \*mutex,
+ const pthread_mutexattr_t \*attr
+ );
+
+**STATUS CODES:**
+
+*EINVAL*
+ The attribute set is not initialized.
+
+*EINVAL*
+ The specified protocol is invalid.
+
+*EAGAIN*
+ The system lacked the necessary resources to initialize another mutex.
+
+*ENOMEM*
+ Insufficient memory exists to initialize the mutex.
+
+*EBUSY*
+ Attempted to reinialize the object reference by mutex, a previously
+ initialized, but not yet destroyed.
+
+**DESCRIPTION:**
+
+**NOTES:**
+
+pthread_mutex_destroy - Destroy a Mutex
+---------------------------------------
+.. index:: pthread_mutex_destroy
+.. index:: destroy a mutex
+
+**CALLING SEQUENCE:**
+
+.. code:: c
+
+ #include <pthread.h>
+ int pthread_mutex_destroy(
+ pthread_mutex_t \*mutex
+ );
+
+**STATUS CODES:**
+
+*EINVAL*
+ The specified mutex is invalid.
+
+*EBUSY*
+ Attempted to destroy the object reference by mutex, while it is locked or
+ referenced by another thread.
+
+**DESCRIPTION:**
+
+**NOTES:**
+
+pthread_mutex_lock - Lock a Mutex
+---------------------------------
+.. index:: pthread_mutex_lock
+.. index:: lock a mutex
+
+**CALLING SEQUENCE:**
+
+.. code:: c
+
+ #include <pthread.h>
+ int pthread_mutex_lock(
+ pthread_mutex_t \*mutex
+ );
+
+**STATUS CODES:**
+
+*EINVAL*
+ The specified mutex is invalid.
+
+*EINVAL*
+ The mutex has the protocol attribute of PTHREAD_PRIO_PROTECT and the
+ priority of the calling thread is higher than the current priority
+ ceiling.
+
+*EDEADLK*
+ The current thread already owns the mutex.
+
+**DESCRIPTION:**
+
+**NOTES:**
+
+pthread_mutex_trylock - Poll to Lock a Mutex
+--------------------------------------------
+.. index:: pthread_mutex_trylock
+.. index:: poll to lock a mutex
+
+**CALLING SEQUENCE:**
+
+.. code:: c
+
+ #include <pthread.h>
+ int pthread_mutex_trylock(
+ pthread_mutex_t \*mutex
+ );
+
+**STATUS CODES:**
+
+*EINVAL*
+ The specified mutex is invalid.
+
+*EINVAL*
+ The mutex has the protocol attribute of PTHREAD_PRIO_PROTECT and the
+ priority of the calling thread is higher than the current priority
+ ceiling.
+
+*EBUSY*
+ The mutex is already locked.
+
+**DESCRIPTION:**
+
+**NOTES:**
+
+pthread_mutex_timedlock - Lock a Mutex with Timeout
+---------------------------------------------------
+.. index:: pthread_mutex_timedlock
+.. index:: lock a mutex with timeout
+
+**CALLING SEQUENCE:**
+
+.. code:: c
+
+ #include <pthread.h>
+ #include <time.h>
+ int pthread_mutex_timedlock(
+ pthread_mutex_t \*mutex,
+ const struct timespec \*timeout
+ );
+
+**STATUS CODES:**
+
+*EINVAL*
+ The specified mutex is invalid.
+
+*EINVAL*
+ The nanoseconds field of timeout is invalid.
+
+*EINVAL*
+ The mutex has the protocol attribute of PTHREAD_PRIO_PROTECT and the
+ priority of the calling thread is higher than the current priority
+ ceiling.
+
+*EDEADLK*
+ The current thread already owns the mutex.
+
+*ETIMEDOUT*
+ The calling thread was unable to obtain the mutex within the specified
+ timeout period.
+
+**DESCRIPTION:**
+
+**NOTES:**
+
+pthread_mutex_unlock - Unlock a Mutex
+-------------------------------------
+.. index:: pthread_mutex_unlock
+.. index:: unlock a mutex
+
+**CALLING SEQUENCE:**
+
+.. code:: c
+
+ #include <pthread.h>
+ int pthread_mutex_unlock(
+ pthread_mutex_t \*mutex
+ );
+
+**STATUS CODES:**
+
+*EINVAL*
+ The specified mutex is invalid.
+
+**DESCRIPTION:**
+
+**NOTES:**
+
+pthread_mutex_setprioceiling - Dynamically Set the Priority Ceiling
+-------------------------------------------------------------------
+.. index:: pthread_mutex_setprioceiling
+.. index:: dynamically set the priority ceiling
+
+**CALLING SEQUENCE:**
+
+.. code:: c
+
+ #include <pthread.h>
+ int pthread_mutex_setprioceiling(
+ pthread_mutex_t \*mutex,
+ int prioceiling,
+ int \*oldceiling
+ );
+
+**STATUS CODES:**
+
+*EINVAL*
+ The oldceiling pointer parameter is invalid.
+
+*EINVAL*
+ The prioceiling parameter is an invalid priority.
+
+*EINVAL*
+ The specified mutex is invalid.
+
+**DESCRIPTION:**
+
+**NOTES:**
+
+pthread_mutex_getprioceiling - Get the Current Priority Ceiling
+---------------------------------------------------------------
+.. index:: pthread_mutex_getprioceiling
+.. index:: get the current priority ceiling
+
+**CALLING SEQUENCE:**
+
+.. code:: c
+
+ #include <pthread.h>
+ int pthread_mutex_getprioceiling(
+ pthread_mutex_t \*mutex,
+ int \*prioceiling
+ );
+
+**STATUS CODES:**
+
+*EINVAL*
+ The prioceiling pointer parameter is invalid.
+
+*EINVAL*
+ The specified mutex is invalid.
+
+**DESCRIPTION:**
+
+**NOTES:**
+
+.. COMMENT: COPYRIGHT (c) 1988-2002.
+
+.. COMMENT: On-Line Applications Research Corporation (OAR).
+
+.. COMMENT: All rights reserved.
+
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