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for ARM devices
OS_ReadLine32
Programmer's Reference Manuals
» Part 15 – SWI Calls
» OS
» OS_ReadLine32
OS_ReadLine32
(SWI &7D)
| Entry | |
|---|---|
| R0 | Buffer |
| R1 | Size of buffer |
| R2 | Lowest char allowed |
| R3 | Highest char allowed |
| R4 | Flags and character to output in bottom byte (if bit 30 set) |
| Exit | |
|---|---|
| R0 | Corrupted |
| R1 | Chars read, excluding Return |
| R2 | Corrupted |
| R3 | Corrupted |
| C flag is set if input is terminated by an escape condition | |
Use
The purpose of this call is to read a line from the current input stream.
Notes
Input is terminated with Return, Ctrl-J or Escape. Delete and Backspace deletes last char entered. Ctrl-U empties buffer.
When the buffer is full, each successive attempt to enter a character results in a Ctrl-G ‘beep’.
The CallASWI module (version 0.03) allows this SWI to be used with RISC OS pre 5.00.