gsh/input/reader
The reader module provides an event-driven terminal polling loop for raw-mode TTY input.
When operating in raw mode, user keystrokes are received as unbuffered input streams.
This module wraps the low-level etch event parser to poll TTY state, filter out non-keyboard
signals (such as window resizes or mouse movements), intercept control chord modifiers
(e.g., Ctrl+L or Ctrl+Left), and map raw events into the shell’s structured Key domain.
Values
pub fn read_key() -> key.KeyPolls the raw TTY stream for the next valid keyboard event.
Polling & CPU Yielding:
- Calls
input.read()to retrieve pending TTY events without thread blocking. - Yields thread execution via
process.sleep(5)when no input is available (None), preventing high CPU utilization during idle REPL prompts. - Recursively discards non-keyboard terminal events (e.g., window size changes, mouse clicks) or stream parse errors until a valid key event is received.