8.6. Removed Directives

8.6.1. TASK_GET_NOTE - Get task notepad entry

Warning

This directive was removed in RTEMS 5.1.

CALLING SEQUENCE:

rtems_status_code rtems_task_get_note(
  rtems_id  id,
  uint32_t  notepad,
  uint32_t *note
);

DIRECTIVE STATUS CODES:

RTEMS_SUCCESSFUL	note value obtained successfully
RTEMS_INVALID_ADDRESS	note parameter is NULL
RTEMS_INVALID_ID	invalid task id
RTEMS_INVALID_NUMBER	invalid notepad location

DESCRIPTION:

This directive returns the note contained in the notepad location of the task specified by id.

NOTES:

This directive will not cause the running task to be preempted.

If id is set to RTEMS_SELF, the calling task accesses its own notepad.

The sixteen notepad locations can be accessed using the constants RTEMS_NOTEPAD_0 through RTEMS_NOTEPAD_15.

Getting a note of a global task which does not reside on the local node will generate a request to the remote node to obtain the notepad entry of the specified task.

8.6.2. TASK_SET_NOTE - Set task notepad entry

Warning

This directive was removed in RTEMS 5.1.

CALLING SEQUENCE:

rtems_status_code rtems_task_set_note(
  rtems_id  id,
  uint32_t  notepad,
  uint32_t  note
);

DIRECTIVE STATUS CODES:

RTEMS_SUCCESSFUL	note set successfully
RTEMS_INVALID_ID	invalid task id
RTEMS_INVALID_NUMBER	invalid notepad location

DESCRIPTION:

This directive sets the notepad entry for the task specified by id to the value note.

NOTES:

If id is set to RTEMS_SELF, the calling task accesses its own notepad.

This directive will not cause the running task to be preempted.

The sixteen notepad locations can be accessed using the constants RTEMS_NOTEPAD_0 through RTEMS_NOTEPAD_15.

Setting a note of a global task which does not reside on the local node will generate a request to the remote node to set the notepad entry of the specified task.

8.6.3. TASK_VARIABLE_ADD - Associate per task variable

Warning

This directive was removed in RTEMS 5.1.

CALLING SEQUENCE:

rtems_status_code rtems_task_variable_add(
    rtems_id  tid,
    void    **task_variable,
    void    (*dtor)(void *)
);

DIRECTIVE STATUS CODES:

RTEMS_SUCCESSFUL	per task variable added successfully
RTEMS_INVALID_ADDRESS	task_variable is NULL
RTEMS_INVALID_ID	invalid task id
RTEMS_NO_MEMORY	invalid task id
RTEMS_ILLEGAL_ON_REMOTE_OBJECT	not supported on remote tasks

DESCRIPTION:

This directive adds the memory location specified by the ptr argument to the context of the given task. The variable will then be private to the task. The task can access and modify the variable, but the modifications will not appear to other tasks, and other tasks’ modifications to that variable will not affect the value seen by the task. This is accomplished by saving and restoring the variable’s value each time a task switch occurs to or from the calling task. If the dtor argument is non-NULL it specifies the address of a ‘destructor’ function which will be called when the task is deleted. The argument passed to the destructor function is the task’s value of the variable.

NOTES:

Task variables increase the context switch time to and from the tasks that own them so it is desirable to minimize the number of task variables. One efficient method is to have a single task variable that is a pointer to a dynamically allocated structure containing the task’s private ‘global’ data. In this case the destructor function could be ‘free’.

Per-task variables are disabled in SMP configurations and this service is not available.

8.6.4. TASK_VARIABLE_GET - Obtain value of a per task variable

Warning

This directive was removed in RTEMS 5.1.

CALLING SEQUENCE:

rtems_status_code rtems_task_variable_get(
    rtems_id  tid,
    void    **task_variable,
    void    **task_variable_value
);

DIRECTIVE STATUS CODES:

RTEMS_SUCCESSFUL	per task variable obtained successfully
RTEMS_INVALID_ADDRESS	task_variable is NULL
RTEMS_INVALID_ADDRESS	task_variable_value is NULL
RTEMS_INVALID_ADDRESS	task_variable is not found
RTEMS_NO_MEMORY	invalid task id
RTEMS_ILLEGAL_ON_REMOTE_OBJECT	not supported on remote tasks

DESCRIPTION:

This directive looks up the private value of a task variable for a specified task and stores that value in the location pointed to by the result argument. The specified task is usually not the calling task, which can get its private value by directly accessing the variable.

NOTES:

If you change memory which task_variable_value points to, remember to declare that memory as volatile, so that the compiler will optimize it correctly. In this case both the pointer task_variable_value and data referenced by task_variable_value should be considered volatile.

Per-task variables are disabled in SMP configurations and this service is not available.

8.6.5. TASK_VARIABLE_DELETE - Remove per task variable

Warning

This directive was removed in RTEMS 5.1.

CALLING SEQUENCE:

rtems_status_code rtems_task_variable_delete(
    rtems_id  id,
    void    **task_variable
);

DIRECTIVE STATUS CODES:

RTEMS_SUCCESSFUL	per task variable deleted successfully
RTEMS_INVALID_ID	invalid task id
RTEMS_NO_MEMORY	invalid task id
RTEMS_INVALID_ADDRESS	task_variable is NULL
RTEMS_ILLEGAL_ON_REMOTE_OBJECT	not supported on remote tasks

DESCRIPTION:

This directive removes the given location from a task’s context.

NOTES:

Per-task variables are disabled in SMP configurations and this service is not available.