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Python Time & Space Complexity

Termios

termios Module¶

The termios module provides POSIX-style terminal I/O control on Unix systems, allowing terminal mode configuration.

Complexity Reference¶

Operation	Time	Space	Notes
`tcgetattr()`	O(1)	O(1)	Get terminal settings; system call
`tcsetattr()`	O(1)	O(1)	Set terminal settings; may block on TCSADRAIN

Terminal Configuration¶

Getting and Setting Terminal Modes¶

import termios
import sys

# Get current settings - O(1)
old_settings = termios.tcgetattr(sys.stdin.fileno())

try:
    # Modify settings
    new_settings = old_settings[:]
    new_settings[3] &= ~termios.ICANON  # Disable canonical mode

    # Apply settings - O(1)
    termios.tcsetattr(
        sys.stdin.fileno(),
        termios.TCSADRAIN,
        new_settings
    )

    # Now stdin is in raw mode
    ch = sys.stdin.read(1)
    print(f"Got: {repr(ch)}")

finally:
    # Restore settings - O(1)
    termios.tcsetattr(
        sys.stdin.fileno(),
        termios.TCSADRAIN,
        old_settings
    )