TCNF

Tiny Command Not Found

`tcnf` (Tiny Command Not Found)

lightweight CLI utility that searches your system’s $PATH for executable matches when a command is misspelled or partially remembered.

Features

Fast & Low Overhead: Written in pure C with minimal dependencies.
Ranked Results: Matches are scored based on quality (Exact > Prefix > Typo > Subsequence > Substring).
Interactive Selection: If multiple matches are found, it presents an interactive menu to choose the correct command.
Complex Matching: Optional “complex” mode for aggressive fuzzy searching (typos and subsequences).
Highly Configurable: Supports result limiting and output reversal.

Installation

Dependencies

GNU make (build-time only)

Building from Source

Clone the repository:

git clone https://codeberg.org/itszariep/tcnf
cd tcnf

Build:

make

Install (defaults to /usr/local):

sudo make install # or doas

The install target can optionally install shell integration and example configuration files. See Installation Options below.

Usage

You can use tcnf directly as a command:

tcnf <command-name>

Options

Option	Long Form	Description
`-c`	`--complex`	Enable typo tolerance and subsequence matching
`-n <num>`	`--limit <num>`	Limit the number of results (max 100)
`-r`	`--reverse`	Reverse the display order
`-p`	`--print`	Print only, non interactive

Shell Integration

tcnf can be hooked into your shell so it runs automatically when a command is not found.

Supported shells

Bash
Zsh
Busybox Ash (Partial, arguments not working)
Fish (Fish crashes)
Tcsh (No available hook for this)

POSIX shells

(bash, busybox ash, zsh)

Per-user installation (recommended)

Add this line to your shell startup file:

[ -r "$HOME/.config/tcnf/tcnf.sh" ] && . "$HOME/.config/tcnf/tcnf.sh"

~/.bashrc (Bash)
~/.profile (Busybox ash)
~/.zshrc (Zsh)

System-wide installation

If installed via make install, the integration script may be placed in:

/etc/profile.d/tcnf.sh

In that case, no manual sourcing is required.

Configuration

Configuration is optional but recommended.

tcnf loads configuration files in the following order (later files override earlier ones):

/etc/tcnf.conf
~/.config/tcnf.conf
Settings bundled with the shell integration script

Available variables

TCNF_USE_PKGFILE=1      # fallback to pkgfile if no match is found
TCNF_DEFAULT_OPTS="-c -r -n 10"
TCNF_PRINTCORRECT=1    # print the corrected command before execution

Example user config:

# ~/.config/tcnf.conf
TCNF_USE_PKGFILE=1
TCNF_DEFAULT_OPTS="-c -r -n 10"
TCNF_PRINTCORRECT=1

Installation Options (Makefile)

The following variables can be overridden when installing:

Variable	Description
`INSTALL_SHELL=0`	Disable POSIX shell integration
`INSTALL_FISH=0`	Disable fish integration
`INSTALL_CONF=0`	Do not install example config files

Example:

sudo make install INSTALL_FISH=0

Scoring Logic

tcnf uses a tiered scoring system to rank matches:

Score = BaseScore + (LengthDifference × 100) + CommandNameLength

Basic matching

Exact match: case-insensitive equality (score 0)
Prefix match: command starts with input (score 10 000)

Complex mode (`-c`)

Typo match: up to 2 character differences (score 20 000)
Subsequence match: characters in order, not contiguous (score 30 000)
Substring match: input occurs anywhere (score 40 000)

Lower scores rank higher.