tfil

A PTY proxy with configurable terminal output filters.

tfil runs a command inside a pseudo-terminal and rewrites its output stream on the way back to your terminal. Use it to clean up specific escape-sequence quirks emitted by interactive TUIs without modifying the program itself.

Installation

% cargo install tfil --locked

Or install a prebuilt binary from GitHub Releases:

% curl --proto '=https' --tlsv1.2 -LsSf https://github.com/knu/tfil/releases/latest/download/tfil-installer.sh | sh

If you use cargo-binstall:

% cargo binstall tfil

Usage

% tfil [OPTIONS] <COMMAND> [ARGS]...

With no filter flags, tfil is a transparent PTY proxy. Each flag enables one filter on the output stream. Hyphenated arguments after <COMMAND> are passed through to the child without needing --:

% tfil --strip-ink-fake-cursor claude --resume

Filters

--strip-cursor-shape — Drop DECSCUSR (CSI Pn SP q) so child programs cannot change the terminal's cursor shape.
--strip-ink-fake-cursor — Strip Ink's fake-cursor sequences (\x1b[7m{grapheme}\x1b[27m and friends), and suppress \x1b[?25l so the terminal's native cursor shows through. Useful with Ink-based TUIs such as Claude Code, Gemini CLI, or ccmanager.
--strip-osc-titles — Drop OSC 0/1/2 sequences (icon name and window title). Other OSCs (4 = palette, 8 = hyperlink, 52 = clipboard, ...) are passed through. Both ST (ESC \) and BEL terminators are recognized.

Composition

When stacking with other PTY wrappers (such as claude-chill), put tfil on the outside so its filters see the original byte stream before any re-rendering layer normalizes it:

% tfil --strip-ink-fake-cursor claude-chill claude

Author

Licensed under the MIT license. See LICENSE for details.