ErsGetTaskId - Get ERS task id for use with ErsEnableTask.
Function
Get ERS task id for use with ErsEnableTask.
Description
Some Systems, such as VxWorks based systems, run all programs in
a common address space. In such systems static and global variables
can be seen by all tasks. To allow tasks to have private copies of
static and global variables it is possible to have such variables saved
and restored during task context switching. Ers uses this technique
to store task specific information. In such systems it is sometimes
necessary to call Ers routines outside the context of a task (say
in an interrupt routine), during which the task specific information
will be unavailable. This routine is used in conjunction with
ErsEnableTask and ErsRestoreTask to make the task specific information
available in such places.
This routine can be used where the task ID returned by ErsStart(3)
is not avaiable. It should be invoked in non-interrupt handler
code to fetch the task id for passing to ErsEnableTask(3).
Language
C
Call
(ErsTaskIdType) = ErsGetTaskId (StatusType *status)
Parameters
(">" input, "!" modified, "W"
workspace, "<" output)
|
! | status | StatusType * | Modified status.
|
|---|
|
Include files
Ers.h
External functions used
None
External values used
None
Function Value
A value which can be passed to ErsEnableTask from an
interrupt handler. If status is non-zero, zero is returned.
Prior requirements
ErsStart should have been called.
Support
Tony Farrell, AAO
Click here for the DRAMA home page and
here for the AAO home page.
For more information, contact tony.farrell@mq.edu.au