| Entry | |
|---|---|
| R1 | Pointer to sub-menu block |
| R2 | X co-ordinate of top left of sub-menu |
| R3 | Y co-ordinate of top left of sub-menu |
| Exit | |
|---|---|
| R0 | Corrupt |
The purpose of this call is to create a sub-menu.
When a sub-menu is requested by the Wimp to be opened, it generates a Message_MenuWarning event code. Applications should respond by using this call to create the sub-menu.
The contents of R1 to R3 are obtained from event code above at offsets +20, +24 & +28