terminal-conio 0.1.0

In-place terminal rendering for Python — a conio.h port with double-buffered dirty-cell rendering

terminal.py · conio.py

In-place terminal rendering for Python

Python 3.8+ Platform Windows · macOS · Linux Deps zero

What is this?

A pure-Python library that replicates the core of C's conio.h / platform_conio.h and adds a double-buffered, dirty-cell terminal renderer on top --- so you can build live-updating TUI applications without flickering, full-screen clears, or third-party dependencies.

Two files, drop them into your project:

• conio.py --- low-level primitives: getch, kbhit, gotoxy, textcolor, clrscr ...

• terminal.py --- high-level double-buffered renderer built on top of conio.py

The Core Idea

Classic terminal rendering problems: either you clear the whole screen every frame (causes flicker) or you manually track every xy position (a thousand gotoxy calls). This library solves both with a front/back buffer pair --- identical to how ncurses works.

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Step What happens Cost

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1. Draw Write into the back Pure Python buffer list writes --- instant

2. Diff Compare back vs Only changed front buffer cells emit cursor moves + chars

3. Flush One One syscall sys.stdout.write() per frame regardless of size

Quick Start

Installation

No pip install --- just copy the files into your project:

cp terminal.py conio.py your_project/

Minimal example

from terminal import Terminal, Color

t = Terminal()

t.print(0, 0, 'Hello, world!', fg=Color.YELLOW)

t.render() # only writes changed cells

# next frame --- only the changed region is redrawn

t.print(0, 0, 'Hello, Python!', fg=Color.YELLOW)

t.render()

Game loop pattern

import time

from terminal import Terminal, Color

from conio import kbhit, getch

with Terminal() as t: # hides cursor automatically

while True:

if kbhit() and getch() == 'q':

break

t.clear() # wipe back buffer (free --- no I/O)

draw_everything(t) # paint into back buffer (free --- no I/O)

t.render() # diff + write only dirty cells

time.sleep(1/30) # ~30 fps

terminal.py API

Constructor

t = Terminal(width=None, height=None)

Auto-detects terminal size via shutil.get_terminal_size(). Pass explicit values to override.

Drawing (writes to back buffer --- zero I/O)

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Method Description

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t.put(col, Write one row, char, fg, character bg, bold)

t.print(col, Write a string row, text, fg, bg, bold)

t.hline(col, Horizontal line row, length,
char, fg, bg)

t.vline(col, Vertical line row, length,
char, fg, bg)

t.box(col, Border box. row, w, h, fg, style='single' bg, style) or 'double'

t.fill(col, Flood-fill a row, w, h, rectangle char, fg, bg)

t.clear(fg, Clear the entire bg) back buffer

Rendering (touches the terminal)

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Method Description

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t.render() Diff buffers and write only changed cells

t.hide_cursor() Hide the terminal cursor

t.show_cursor() Restore the terminal cursor

t.resize() Re-detect size and rebuild buffers

Context manager

Using with Terminal() as t: automatically hides the cursor on entry and restores it (plus moves the cursor below the drawn area) on exit --- even if an exception is raised.

conio.py API

Low-level primitives that mirror conio.h. Can be used standalone without terminal.py.

Input

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Function conio.h Description equivalent

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getch() getch() Read one char, no Enter, no echo

getche() getche() Read one char, no Enter, echoes char

kbhit() kbhit() True if a key is waiting in the buffer

putch(ch) putch(c) Write one character to stdout

ungetch(ch) ungetch(c) Push character back into input buffer

getpass_conio(prompt) --- Password input (hides chars, supports backspace)

Screen

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Function conio.h Description equivalent

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clrscr() clrscr() Clear the terminal screen

gotoxy(x, y) gotoxy(x, y) Move cursor (1-based, like conio.h)

wherex() wherex() Current cursor column (1-based)

wherey() wherey() Current cursor row (1-based)

Color

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Function conio.h Description equivalent

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textcolor(c) textcolor(c) Set foreground color using Color.*

textbackground(c) textbackground(c) Set background color using Color.*

normvideo() normvideo() Reset to terminal defaults

highvideo() highvideo() Enable bright/bold text

lowvideo() lowvideo() Switch to dim variant of current color

cprintf(text, fg, cprintf(...) Print with bg, end) colors, then restore previous colors

cputs(text) cputs(s) Write string to stdout, no newline

Color constants (Color.*)

16 named constants matching the classic DOS/conio palette:

BLACK BLUE GREEN CYAN RED MAGENTA YELLOW WHITE DARK_GRAY LIGHT_BLUE LIGHT_GREEN LIGHT_CYAN LIGHT_RED LIGHT_MAGENTA BRIGHT_YELLOW BRIGHT_WHITE

Platform Notes

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Feature Windows macOS / Linux

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Input (getch msvcrt termios + tty / kbhit)

Cursor Win32 Console API ANSI DSR escape position (ctypes) \033[6n

Color SetConsoleTextAttribute ANSI escape sequences

Cursor SetConsoleCursorInfo \033[?25l / show/hide \033[?25h

Screen clear os.system('cls') \033[2J\033[H

Note: terminal.py uses ANSI escape sequences for all rendering, so it targets any terminal emulator that supports ANSI (virtually everything on macOS/Linux; Windows Terminal and modern cmd.exe on Windows).

Files

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File Purpose

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terminal.py Double-buffered renderer --- main library

conio.py Low-level conio.h primitives

demo_terminal.py Live demo: bouncing ball, sine wave, clock, progress bar

demo_conio.py Color palette, cursor positioning, password input demo