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for ARM devices
OS_Byte 2
Programmer's Reference Manuals
» Part 15 – SWI Calls
» OS
» OS_Byte
» OS_Byte 2
OS_Byte 2
(SWI &06)
| Entry | |
|---|---|
| R0 | 2 |
| R1 | Stream selection |
| Exit | |
|---|---|
| R0 | Preserved |
| R1 | Value before being overwritten |
| R2 | Corrupted |
Use
The purpose of this call is to select the device from which all subsequent input is taken by OS_ReadC.
Notes
On exit only 0 or 1 can be returned, so 0 may also mean 2. The state of this variable can be read with OS_Byte 177.
If Exec is enabled (see OS_Byte 198) then the Exec file handle is used as the current input stream.