OS_UpCall 257 (changes)
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OS SWI Calls
» OS_UpCall
» OS_UpCall 257
OS_UpCall 257
(SWI &33)
| Entry | |
|---|---|
| R0 | 257 (&101) |
| R1 | Amount that application space is going to change by |
| Exit | |
|---|---|
| R0 | 0 to permit memory moved, else preserved |
| R1 | Preserved |
Use
The purpose of this call is to call inform your application that the Operating System would like to move memory
Notes
This call is made just before OS_ChangeDynamicArea tries to move memory. The call is only made if the currently active object is in the application space. It calls the UpCall vector. By default default, (if you don’t claim the vector) the memory isn’t moved.
Your routine must shuffle your application’s workspace so that the memory can go ahead. It must then set R0 = 0, and pass on the call to the vector.
See also
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