Wimp_Poll (changes)
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WindowManager
» SWI Calls
» Wimp_Poll
Wimp_Poll
(SWI &400C7)
| Entry | |
|---|---|
| R0 | Poll Mask |
| R1 | Pointer to 256 byte block |
| R3 | Pointer to pollword in RMA (if R0 bit22 is set) |
| Exit | |
|---|---|
| R0 | Reason Code |
| R1 | Pointer to block of data |
| R2 | Senders task handle |
Use
The purpose of this call is poll the Wimp to check for any system wide events that the application may need to respond to. i.e. windows, menus, mouse, keyboard handling.
Notes
Every application must have poll loop whereby it calls Wimp_Poll.
The call returns specific event codes, and the application must then decide whether it wishes to respond to it.
If upon calling Wimp_Poll an escape condition is detected, the Wimp will cancel the condition and disable future escape conditions.
Any errors that occur inside Wimp_Poll are reported by the Wimp itself and not passed back to the applications. The only exception to this rule is when an error was caused due to bad parameter usage.
See also
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