Filter_RegisterPostFilter (changes)
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FilterManager
» SWI Calls?SWI Calls
» Filter_RegisterPostFilter
Filter_RegisterPostFilter
(SWI &42641)
| Entry | |
|---|---|
| R0 | Pointer to zero terminated filter name |
| R1 | Address of Post Filter Code |
| R2 | Value to be passed to R12 |
| R3 | Task handle of task to which filter is applied, or 0 for all tasks |
| R4 | Poll Mask (value of 1 masks the event – same as Wimp_Poll) |
| Exit |
|---|
| All registers preserved |
Use
The purpose of this call is to add a new filter to the list of post-filters.
Notes
The filter routine at the address pointed to by R1 will be called whenever the Wimp is about to return from Wimp_Poll. When registering the filter use R3 to control whether the filter is called for all tasks or only for a specific task.
See Post Filter Code for details of how the filter routine must operate.
See also
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