bat/README.md

A cat(1) clone with syntax highlighting and Git integration.

Key Features • How To Use • Installation • Customization • Project goals, alternatives

Syntax highlighting

bat supports syntax highlighting for a large number of programming and markup languages:

Git integration

bat communicates with git to show modifications with respect to the index (see left side bar):

Automatic paging

bat can pipe its own output to less if the output is too large for one screen.

File concatenation

Oh.. you can also use it to concatenate files 😉. Whenever bat detects a non-interactive terminal, it will fall back to printing the plain file contents.

How to use

Display a single file on the terminal

> bat README.md

Display multiple files at once

> bat src/*.rs

Read from stdin, determine the syntax automatically

> curl -s https://sh.rustup.rs | bat

Read from stdin, specify the language explicitly

> yaml2json .travis.yml | json_pp | bat -l json

As a replacement for cat:

bat > note.md  # quickly create a new file

bat header.md content.md footer.md > document.md

bat -n main.rs  # show line numbers (only)

bat f - g  # output 'f', then stdin, then 'g'.

Installation

On Ubuntu

... and other Debian-based Linux distributions.

Download the latest .deb package from the release page and install it via:

sudo dpkg -i bat_0.7.1_amd64.deb  # adapt version number and architecture

On Arch Linux

You can install the bat package from the official sources:

pacman -S bat

On Void Linux

You can install bat via xbps-install:

xbps-install -S bat

On FreeBSD

You can install a precompiled bat package with pkg:

pkg install bat

or build it on your own from the FreeBSD ports:

cd /usr/ports/textproc/bat
make install

Via nix

You can install bat using the nix package manager:

nix-env -i bat

On macOS

You can install bat with Homebrew:

brew install bat

On Windows

You can download prebuilt binaries from the Release page, or install it with scoop:

scoop install bat

See below for notes.

Via Docker

There is a Docker image that you can use to run bat in a container:

docker pull danlynn/bat
alias bat='docker run -it --rm -e BAT_THEME -e BAT_STYLE -e BAT_TABS -v "$(pwd):/myapp" danlynn/bat'

Via Ansible

You can install bat with Ansible:

# Install role on local machine
ansible-galaxy install aeimer.install_bat

---
# Playbook to install bat
- host: all
  roles:
    - aeimer.install_bat

• Ansible Galaxy
• GitHub

This should work with the following distributions:

• Debian/Ubuntu
• ARM (eg. Raspberry PI)
• Arch Linux
• Void Linux
• FreeBSD
• MacOS

From binaries

Check out the Release page for prebuilt versions of bat for many different architectures. Statically-linked binaries are available, just look for releases with musl in the name on the releases page.

From source

If you want to build bat from source, you need Rust 1.27 or higher. You can then use cargo to build everything:

cargo install bat

You may have to install cmake and the libz development package (libz-dev or libz-devel) in order for the build to succeed.

Customization

Highlighting theme

Use bat --list-themes to get a list of all available themes for syntax highlighting. To select the TwoDark theme, call bat with the --theme=TwoDark option or set the BAT_THEME environment variable to TwoDark. Use export BAT_THEME="TwoDark" in your shell's startup file to make the change permanent.

If you want to preview the different themes on a custom file, you can use the following command (you need fzf for this):

bat --list-themes | fzf --preview="bat --theme={} --color=always /path/to/file"

bat looks good on a dark background by default. However, if your terminal uses a light background, some themes will work better for you. For example, the GitHub theme is made for light backgrounds. To set your theme permanently, put export BAT_THEME="GitHub" in your shell's startup file (like .bashrc). If you'd like to see the other available themes, run bat --list-themes. You can also make your own theme by following the 'Adding new themes' section below.

Output style

You can use the --style option to control the appearance of bats output. You can use --style=numbers,changes, for example, to show only Git changes and line numbers but no grid and no file header. Use the BAT_STYLE environment variable to make these changes permanent.

Adding new syntaxes / language definitions

bat uses the excellent syntect library for syntax highlighting. syntect can read any Sublime Text .sublime-syntax file and theme. To add new syntax definitions, do the following.

Create a folder with syntax definition files:

BAT_CONFIG_DIR="$(bat cache --config-dir)"

mkdir -p "$BAT_CONFIG_DIR/syntaxes"
cd "$BAT_CONFIG_DIR/syntaxes"

# Put new '.sublime-syntax' language definition files
# in this folder (or its subdirectories), for example:
git clone https://github.com/tellnobody1/sublime-purescript-syntax

Now use the following command to parse these files into a binary cache:

bat cache --init

Finally, use bat --list-languages to check if the new languages are available.

If you ever want to go back to the default settings, call:

bat cache --clear

Adding new themes

This works very similar to how we add new syntax definitions.

First, create a folder with the new syntax highlighting themes:

BAT_CONFIG_DIR="$(bat cache --config-dir)"

mkdir -p "$BAT_CONFIG_DIR/themes"
cd "$BAT_CONFIG_DIR/themes"

# Download a theme in '.tmTheme' format, for example:
git clone https://github.com/greggb/sublime-snazzy

# Update the binary cache
bat cache --init

Finally, use bat --list-themes to check if the new themes are available.

Using a different pager

bat uses the pager that is specified in the PAGER environment variable. If this variable is not set, less is used by default. If you want to use a different pager, you can either modify the PAGER variable or set the BAT_PAGER environment variable to override what is specified in PAGER.

If you want to pass command-line arguments to the pager, you need to create a small shell script as a wrapper, for example

#!/bin/bash

less --tabs 4 -R "$@"

(put this in a file ~/.bat-pager.sh, make it executable chmod +x ~/.bat-pager.sh and use export BAT_PAGER="$HOME/.bat-pager.sh" in your shells rc file)

Note: By default, if the pager is set to less, bat will pass the following command line options to the pager: -R/--RAW-CONTROL-CHARS, -F/--quit-if-one-screen and -X/--no-init. The first (-R) is needed to interpret ANSI colors correctly. The second option (-F) instructs less to exit immediately if the output size is smaller than the vertical size of the terminal. This is convenient for small files because you do not have to press q to quit the pager. The third option (-X) is needed to fix a bug with the --quit-if-one-screen feature in old versions of less. Unfortunately, it also breaks mouse-wheel support in less. If you want to enable mouse-wheel scrolling, you can either pass just -R (as in the example above, this will disable the quit-if-one-screen feature), or you can use a recent version of less and pass -RF which will hopefully enable both quit-if-one-screen and mouse-wheel scrolling.

If scrolling still doesn't work for you, you can try to pass the -S option in addition.

Using bat on Windows

bat mostly works out-of-the-box on Windows, but a few features may need extra configuration.

Paging

Windows only includes a very limited pager in the form of more. You can download a Windows binary for less from its homepage or through Chocolatey. To use it, place the binary in a directory in your PATH or define an environment variable.

Colours

Windows 10 natively supports colours in both conhost.exe (Command Prompt) and PowerShell since v1511, as well as in newer versions of bash. On earlier versions of Windows, you can use Cmder, which includes ConEmu.

Note: The Git and MSYS versions of less do not correctly interpret colours on Windows. If you don’t have any other pagers installed, you can disable paging entirely by passing --paging=never or by setting BAT_PAGER to an empty string.

Cygwin

bat on Windows does not natively support Cygwin's unix-style paths (/cygdrive/*). When passed an absolute cygwin path as an argument, bat will encounter the following error: The system cannot find the path specified. (os error 3)

This can be solved by creating a wrapper or adding the following function to your .bash_profile file:

bat() {
    local index
    local args=("$@")
    for index in $(seq 0 ${#args[@]}) ; do
        case "${args[index]}" in
        -*) continue;;
        *)  [ -e "${args[index]}" ] && args[index]="$(cygpath --windows "${args[index]}")";;
        esac
    done
    command bat "${args[@]}"
}

Troubleshooting

Terminals & colors

bat handles terminals with and without truecolor support. However, the colors in the syntax highlighting themes are not optimized for 8-bit colors and it is therefore strongly recommended that you use a terminal with 24-bit truecolor support (terminator, konsole, iTerm2, ...). See this article for more details and a full list of terminals with truecolor support.

Make sure that your truecolor terminal sets the COLORTERM variable to either truecolor or 24bit. Otherwise, bat will not be able to determine whether or not 24-bit escape sequences are supported (and fall back to 8-bit colors).

Line numbers and grid are hardly visible

Please try a different theme (see bat --list-themes for a list). The OneHalfDark and OneHalfLight themes provide grid and line colors that are brighter.

Development

# Recursive clone to retrieve all submodules
git clone --recursive https://github.com/sharkdp/bat

# Build (debug version)
cd bat
cargo build

# Run unit tests and integration tests
cargo test

# Install (release version)
cargo install

# Build a bat binary with modified syntaxes and themes
bash assets/create.sh
cargo install -f

Project goals and alternatives

bat tries to achieve the following goals:

• Provide beautiful, advanced syntax highlighting
• Integrate with Git to show file modifications
• Be a drop-in replacement for (POSIX) cat
• Offer a user-friendly command-line interface

There are a lot of alternatives, if you are looking for similar programs. See this document for a comparison.