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OS_ChangeDynamicArea
Programmer's Reference Manuals
» Part 15 – SWI Calls
» OS
» OS_ChangeDynamicArea
OS_ChangeDynamicArea
(SWI &2A)
| Entry | |
|---|---|
| R0 | Area to alter |
| R1 | Amount to move in bytes (signed integer) |
| Exit | |
|---|---|
| R0 | Preserved |
| R1 | Amount the area has changed in bytes (unsigned) |
Use
The purpose of this call is change the size of a dynamic area.
Notes
Let you enlarge (R1 positive) or shrink (R1 negative) the selected area.
If you need to release as much space as possible from an area, try to reduce its size by 16 MBytes.
Note, that normally this cannot be used while the application work area is being used; main purpose is for the OS, modules and utilities.
This SWI issues OS_UpCall 257 (moving memory); if the upcall is claimed when an application is running in the application workspace then the memory movement is allowed.
See also
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