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OS_GBPB 10
Programmer's Reference Manuals
» Part 15 – SWI Calls
» OS
» OS_GBPB
» OS_GBPB 10
OS_ GBPB 10
(SWI &0C)
| Entry | |
|---|---|
| R0 | 10 |
| R1 | Pointer to directory name |
| R2 | Pointer to buffer |
| R3 | Number of objects to read |
| R4 | Where to start, 0 for first time |
| R5 | Length of buffer |
| R6 | Wildcarded name to match (if 0 “*” is used) |
| Exit | |
|---|---|
| R0 | Preserved |
| R1 | Preserved |
| R2 | Buffer |
| R3 | Number of objects read |
| R4 | Where to continue, or -1 for no more |
| C flag clear if R3 = 0, else set | |
Use
The purpose of this call is to read entries and file information from a specified directory, and return data in a buffer.
Notes
The correct code structure to call this SWI is:
repeat
{
call OS_GBPB 10
if (R3 <> 0)
{
process buffer
}
} until (R4 = -1)
as it is legal to return R3 = 0 before the end of the directory. Also, do not assume anything about the value in R4 – Filer_Action assumes that it increases by one for each entry read and comes horribly unstuck.