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Dynamic Area PreShrink (changes)
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OS_DynamicArea
» Dynamic Area Handler Code
» Dynamic Area PreShrink
| Entry | |
|---|---|
| R0 | 2 (handler reason) |
| R3 | Amount area is shrinking by (bytes), i.e. R2*R5 |
| R4 | Current size of area (bytes) |
| R5 | Page size (bytes) |
| R12 | Workspace pointer passed to OS_DynamicArea 0 or base of area |
| Exit | (Success) |
|---|---|
| R3 | Amount to shrink by |
| All other registers preserved | |
| V clear |
| Exit | (Error) |
|---|---|
| R0 | Pointer to error block, or 0 for a default error to be used |
| R3 | 0 |
| All other registers preserved | |
| V set |
Use
This call is issued by the kernel prior to shrinking a dynamic area. It allows the owner of the area to limit how much the area is shrunk by, or to reject the request completely.
The returned R3 value must be less than or equal to the input value.
See also
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