A fast and easily customised operating system
for ARM devices
OS_ReadLine
Programmer's Reference Manuals
» Part 15 – SWI Calls
» OS
» OS_ReadLine
OS_ReadLine
(SWI &0E)
| Entry | |
|---|---|
| R0 | Buffer + flags |
| R1 | Lowest char allowed |
| R2 | Lowest char allowed |
| R3 | Highest char allowed |
| R4 | Character to output (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’.