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tesseract

Thu, 11 Sep 2025 15:31:10 +0800

tesseract-ocr/tesseract

Tesseract OCR

Tesseract OCR

About

This package contains an OCR engine - libtesseract and a command line program - tesseract.

Tesseract 4 adds a new neural net (LSTM) based OCR engine which is focused on line recognition, but also still supports the legacy Tesseract OCR engine of Tesseract 3 which works by recognizing character patterns. Compatibility with Tesseract 3 is enabled by using the Legacy OCR Engine mode (–oem 0). It also needs traineddata files which support the legacy engine, for example those from the tessdata repository.

Stefan Weil is the current lead developer. Ray Smith was the lead developer until 2018. The maintainer is Zdenko Podobny. For a list of contributors see AUTHORS and GitHub’s log of contributors.

Tesseract has unicode (UTF-8) support, and can recognize more than 100 languages “out of the box”.

Tesseract supports various image formats including PNG, JPEG and TIFF.

Tesseract supports various output formats: plain text, hOCR (HTML), PDF, invisible-text-only PDF, TSV, ALTO and PAGE.

You should note that in many cases, in order to get better OCR results, you’ll need to improve the quality of the image you are giving Tesseract.

This project does not include a GUI application. If you need one, please see the 3rdParty documentation.

Tesseract can be trained to recognize other languages. See Tesseract Training for more information.

Brief history

Tesseract was originally developed at Hewlett-Packard Laboratories Bristol UK and at Hewlett-Packard Co, Greeley Colorado USA between 1985 and 1994, with some more changes made in 1996 to port to Windows, and some C++izing in 1998. In 2005 Tesseract was open sourced by HP. From 2006 until November 2018 it was developed by Google.

Major version 5 is the current stable version and started with release 5.0.0 on November 30, 2021. Newer minor versions and bugfix versions are available from GitHub.

Latest source code is available from main branch on GitHub. Open issues can be found in issue tracker, and planning documentation.

See Release Notes and Change Log for more details of the releases.

Installing Tesseract

You can either Install Tesseract via pre-built binary package or build it from source.

Before building Tesseract from source, please check that your system has a compiler which is one of the supported compilers.

Running Tesseract

Basic command line usage:

tesseract imagename outputbase [-l lang] [--oem ocrenginemode] [--psm pagesegmode] [configfiles...]

For more information about the various command line options use tesseract --help or man tesseract.

Examples can be found in the documentation.

For developers

Developers can use libtesseract C or C++ API to build their own application. If you need bindings to libtesseract for other programming languages, please see the wrapper section in the AddOns documentation.

Documentation of Tesseract generated from source code by doxygen can be found on tesseract-ocr.github.io.

Support

Before you submit an issue, please review the guidelines for this repository.

For support, first read the documentation, particularly the FAQ to see if your problem is addressed there. If not, search the Tesseract user forum, the Tesseract developer forum and past issues, and if you still can’t find what you need, ask for support in the mailing-lists.

Mailing-lists:

tesseract-ocr - For tesseract users.
tesseract-dev - For tesseract developers.

Please report an issue only for a bug, not for asking questions.

License

The code in this repository is licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

   http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.

NOTE: This software depends on other packages that may be licensed under different open source licenses.

Tesseract uses Leptonica library which essentially uses a BSD 2-clause license.

Dependencies

Tesseract uses Leptonica library for opening input images (e.g. not documents like pdf). It is suggested to use leptonica with built-in support for zlib, png and tiff (for multipage tiff).

Latest Version of README

For the latest online version of the README.md see:

https://github.com/tesseract-ocr/tesseract/blob/main/README.md

coreutils

Tue, 09 Sep 2025 15:29:32 +0800

uutils/coreutils

uutils coreutils

uutils coreutils is a cross-platform reimplementation of the GNU coreutils in Rust. While all programs have been implemented, some options might be missing or different behavior might be experienced.

To install it:

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cargo install coreutils
~/.cargo/bin/coreutils

Goals

uutils coreutils aims to be a drop-in replacement for the GNU utils. Differences with GNU are treated as bugs.

Our key objectives include:

Matching GNU’s output (stdout and error code) exactly
Better error messages
Providing comprehensive internationalization support (UTF-8)
Improved performances
Extensions when relevant (example: –progress)

uutils aims to work on as many platforms as possible, to be able to use the same utils on Linux, macOS, Windows and other platforms. This ensures, for example, that scripts can be easily transferred between platforms.

Documentation

uutils has both user and developer documentation available:

Both can also be generated locally, the instructions for that can be found in the coreutils docs repository.

Use weblate/rust-coreutils to translate the Rust coreutils into your language.

Requirements

Rust (cargo, rustc)
GNU Make (optional)

Rust Version

uutils follows Rust’s release channels and is tested against stable, beta and nightly. The current Minimum Supported Rust Version (MSRV) is 1.85.0.

Building

There are currently two methods to build the uutils binaries: either Cargo or GNU Make.

Building the full package, including all documentation, requires both Cargo and GNU Make on a Unix platform.

For either method, we first need to fetch the repository:

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git clone https://github.com/uutils/coreutils
cd coreutils

Cargo

Building uutils using Cargo is easy because the process is the same as for every other Rust program:

`1`	`cargo build --release`

This command builds the most portable common core set of uutils into a multicall (BusyBox-type) binary, named ‘coreutils’, on most Rust-supported platforms.

Additional platform-specific uutils are often available. Building these expanded sets of uutils for a platform (on that platform) is as simple as specifying it as a feature:

cargo build --release --features macos
# or ...
cargo build --release --features windows
# or ...
cargo build --release --features unix

If you don’t want to build every utility available on your platform into the final binary, you can also specify which ones you want to build manually. For example:

`1`	`cargo build --features "base32 cat echo rm" --no-default-features`

If you don’t want to build the multicall binary and would prefer to build the utilities as individual binaries, that is also possible. Each utility is contained in its own package within the main repository, named “uu_UTILNAME”. To build individual utilities, use cargo to build just the specific packages (using the --package [aka -p] option). For example:

`1`	`cargo build -p uu_base32 -p uu_cat -p uu_echo -p uu_rm`

GNU Make

Building using make is a simple process as well.

To simply build all available utilities:

make

In release mode:

`1`	`make PROFILE=release`

To build all but a few of the available utilities:

`1`	`make SKIP_UTILS='UTILITY_1 UTILITY_2'`

To build only a few of the available utilities:

`1`	`make UTILS='UTILITY_1 UTILITY_2'`

Installation

Install with Cargo

Likewise, installing can simply be done using:

`1`	`cargo install --path . --locked`

This command will install uutils into Cargo’s bin folder (e.g. $HOME/.cargo/bin).

This does not install files necessary for shell completion or manpages. For manpages or shell completion to work, use GNU Make or see Manually install shell completions/Manually install manpages.

Install with GNU Make

To install all available utilities:

`1`	`make install`

To install using sudo switch -E must be used:

`1`	`sudo -E make install`

To install all but a few of the available utilities:

`1`	`make SKIP_UTILS='UTILITY_1 UTILITY_2' install`

To install only a few of the available utilities:

`1`	`make UTILS='UTILITY_1 UTILITY_2' install`

To install every program with a prefix (e.g. uu-echo uu-cat):

`1`	`make PROG_PREFIX=PREFIX_GOES_HERE install`

To install the multicall binary:

`1`	`make MULTICALL=y install`

Set install parent directory (default value is /usr/local):

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# DESTDIR is also supported
make PREFIX=/my/path install

Installing with make installs shell completions for all installed utilities for bash, fish and zsh. Completions for elvish and powershell can also be generated; See Manually install shell completions.

To skip installation of completions and manpages:

`1`	`make COMPLETIONS=n MANPAGES=n install`

Manually install shell completions

The coreutils binary can generate completions for the bash, elvish, fish, powershell and zsh shells. It prints the result to stdout.

The syntax is:

`1`	`cargo run completion <utility> <shell>`

So, to install completions for ls on bash to /usr/local/share/bash-completion/completions/ls, run:

`1`	`cargo run completion ls bash > /usr/local/share/bash-completion/completions/ls`

Manually install manpages

To generate manpages, the syntax is:

`1`	`cargo run manpage <utility>`

So, to install the manpage for ls to /usr/local/share/man/man1/ls.1 run:

`1`	`cargo run manpage ls > /usr/local/share/man/man1/ls.1`

Un-installation

Un-installation differs depending on how you have installed uutils. If you used Cargo to install, use Cargo to uninstall. If you used GNU Make to install, use Make to uninstall.

Uninstall with Cargo

To uninstall uutils:

`1`	`cargo uninstall coreutils`

Uninstall with GNU Make

To uninstall all utilities:

`1`	`make uninstall`

To uninstall every program with a set prefix:

`1`	`make PROG_PREFIX=PREFIX_GOES_HERE uninstall`

To uninstall the multicall binary:

`1`	`make MULTICALL=y uninstall`

To uninstall from a custom parent directory:

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# DESTDIR is also supported
make PREFIX=/my/path uninstall

GNU test suite compatibility

Below is the evolution of how many GNU tests uutils passes. A more detailed breakdown of the GNU test results of the main branch can be found in the user manual.

See https://github.com/orgs/uutils/projects/1 for the main meta bugs (many are missing).

Contributing

To contribute to uutils, please see CONTRIBUTING.

License

uutils is licensed under the MIT License - see the LICENSE file for details

GNU Coreutils is licensed under the GPL 3.0 or later.

spotify-downloader

Tue, 26 Aug 2025 15:29:12 +0800

spotDL/spotify-downloader

spotDL v4

spotDL finds songs from Spotify playlists on YouTube and downloads them - along with album art, lyrics and metadata.

spotDL: The fastest, easiest and most accurate command-line music downloader.

Read the documentation on ReadTheDocs!

Installation

Refer to our Installation Guide for more details.

Python (Recommended Method)

spotDL can be installed by running pip install spotdl.
To update spotDL run pip install --upgrade spotdl

On some systems you might have to change pip to pip3.

Other options

Prebuilt executable
- You can download the latest version from the Releases Tab
On Termux
- curl -L https://raw.githubusercontent.com/spotDL/spotify-downloader/master/scripts/termux.sh | sh
Arch
- There is an Arch User Repository (AUR) package for spotDL.

Docker

Build image:
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docker build -t spotdl .
Launch container with spotDL parameters (see section below). You need to create mapped volume to access song files
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docker run --rm -v $(pwd):/music spotdl download [trackUrl]

Build from source

git clone https://github.com/spotDL/spotify-downloader && cd spotify-downloader
pip install uv
uv sync
uv run scripts/build.py

An executable is created in spotify-downloader/dist/.

Installing FFmpeg

FFmpeg is required for spotDL. If using FFmpeg only for spotDL, you can simply install FFmpeg to your spotDL installation directory: spotdl --download-ffmpeg

We recommend the above option, but if you want to install FFmpeg system-wide, follow these instructions

Windows Tutorial
OSX - brew install ffmpeg
Linux - sudo apt install ffmpeg or use your distro’s package manager

Usage

Using SpotDL without options:

`1`	`spotdl [urls]`

You can run spotDL as a package if running it as a script doesn’t work:

`1`	`python -m spotdl [urls]`

General usage:

`1`	`spotdl [operation] [options] QUERY`

There are different operations spotDL can perform. The default is download, which simply downloads the songs from YouTube and embeds metadata.

The query for spotDL is usually a list of Spotify URLs, but for some operations like sync, only a single link or file is required. For a list of all options use spotdl -h

Supported operations

save: Saves only the metadata from Spotify without downloading anything.
- Usage: spotdl save [query] --save-file {filename}.spotdl
web: Starts a web interface instead of using the command line. However, it has limited features and only supports downloading single songs.
url: Get direct download link for each song from the query.
- Usage: spotdl url [query]
sync: Updates directories. Compares the directory with the current state of the playlist. Newly added songs will be downloaded and removed songs will be deleted. No other songs will be downloaded and no other files will be deleted.
- Usage: spotdl sync [query] --save-file {filename}.spotdl
  
  This create a new sync file, to update the directory in the future, use:
  
  spotdl sync {filename}.spotdl
meta: Updates metadata for the provided song files.

Music Sourcing and Audio Quality

spotDL uses YouTube as a source for music downloads. This method is used to avoid any issues related to downloading music from Spotify.

Note Users are responsible for their actions and potential legal consequences. We do not support unauthorized downloading of copyrighted material and take no responsibility for user actions.

Audio Quality

spotDL downloads music from YouTube and is designed to always download the highest possible bitrate; which is 128 kbps for regular users and 256 kbps for YouTube Music premium users.

Check the Audio Formats page for more info.

Contributing

Interested in contributing? Check out our CONTRIBUTING.md to find resources around contributing along with a guide on how to set up a development environment.

Join our amazing community as a code contributor

License

This project is Licensed under the MIT License.

the-art-of-command-line

Sun, 03 Aug 2025 15:29:56 +0800

jlevy/the-art-of-command-line

🌍 Čeština ∙ Deutsch ∙ Ελληνικά ∙ English ∙ Español ∙ Français ∙ Indonesia ∙ Italiano ∙ 日本語 ∙ 한국어 ∙ polski ∙ Português ∙ Română ∙ Русский ∙ Slovenščina ∙ Українська ∙ 简体中文 ∙ 繁體中文

The Art of Command Line

Note: I’m planning to revise this and looking for a new co-author to help with expanding this into a more comprehensive guide. While it’s very popular, it could be broader and a bit deeper. If you like to write and are close to being an expert on this material and willing to consider helping, please drop me a note at josh (0x40) holloway.com. –jlevy, Holloway. Thank you!

Fluency on the command line is a skill often neglected or considered arcane, but it improves your flexibility and productivity as an engineer in both obvious and subtle ways. This is a selection of notes and tips on using the command-line that we’ve found useful when working on Linux. Some tips are elementary, and some are fairly specific, sophisticated, or obscure. This page is not long, but if you can use and recall all the items here, you know a lot.

This work is the result of many authors and translators. Some of this originally appeared on Quora, but it has since moved to GitHub, where people more talented than the original author have made numerous improvements. Please submit a question if you have a question related to the command line. Please contribute if you see an error or something that could be better!

Basics

Learn basic Bash. Actually, type man bash and at least skim the whole thing; it’s pretty easy to follow and not that long. Alternate shells can be nice, but Bash is powerful and always available (learning only zsh, fish, etc., while tempting on your own laptop, restricts you in many situations, such as using existing servers).
Learn at least one text-based editor well. The nano editor is one of the simplest for basic editing (opening, editing, saving, searching). However, for the power user in a text terminal, there is no substitute for Vim (vi), the hard-to-learn but venerable, fast, and full-featured editor. Many people also use the classic Emacs, particularly for larger editing tasks. (Of course, any modern software developer working on an extensive project is unlikely to use only a pure text-based editor and should also be familiar with modern graphical IDEs and tools.)
Finding documentation:
- Know how to read official documentation with man (for the inquisitive, man man lists the section numbers, e.g. 1 is “regular” commands, 5 is files/conventions, and 8 are for administration). Find man pages with apropos.
- Know that some commands are not executables, but Bash builtins, and that you can get help on them with help and help -d. You can find out whether a command is an executable, shell builtin or an alias by using type command.
- curl cheat.sh/command will give a brief “cheat sheet” with common examples of how to use a shell command.
Learn about redirection of output and input using > and < and pipes using |. Know > overwrites the output file and >> appends. Learn about stdout and stderr.
Learn about file glob expansion with * (and perhaps ? and […]) and quoting and the difference between double " and single ' quotes. (See more on variable expansion below.)
Be familiar with Bash job management: &, ctrl-z, ctrl-c, jobs, fg, bg, kill, etc.
Know ssh, and the basics of passwordless authentication, via ssh-agent, ssh-add, etc.
Basic file management: ls and ls -l (in particular, learn what every column in ls -l means), less, head, tail and tail -f (or even better, less +F), ln and ln -s (learn the differences and advantages of hard versus soft links), chown, chmod, du (for a quick summary of disk usage: du -hs *). For filesystem management, df, mount, fdisk, mkfs, lsblk. Learn what an inode is (ls -i or df -i).
Basic network management: ip or ifconfig, dig, traceroute, route.
Learn and use a version control management system, such as git.
Know regular expressions well, and the various flags to grep/egrep. The -i, -o, -v, -A, -B, and -C options are worth knowing.
Learn to use apt-get, yum, dnf or pacman (depending on distro) to find and install packages. And make sure you have pip to install Python-based command-line tools (a few below are easiest to install via pip).

Everyday use

In Bash, use Tab to complete arguments or list all available commands and ctrl-r to search through command history (after pressing, type to search, press ctrl-r repeatedly to cycle through more matches, press Enter to execute the found command, or hit the right arrow to put the result in the current line to allow editing).
In Bash, use ctrl-w to delete the last word, and ctrl-u to delete the content from current cursor back to the start of the line. Use alt-b and alt-f to move by word, ctrl-a to move cursor to beginning of line, ctrl-e to move cursor to end of line, ctrl-k to kill to the end of the line, ctrl-l to clear the screen. See man readline for all the default keybindings in Bash. There are a lot. For example alt-. cycles through previous arguments, and alt-* expands a glob.
Alternatively, if you love vi-style key-bindings, use set -o vi (and set -o emacs to put it back).
For editing long commands, after setting your editor (for example export EDITOR=vim), ctrl-x ctrl-e will open the current command in an editor for multi-line editing. Or in vi style, escape-v.
To see recent commands, use history. Follow with !n (where n is the command number) to execute again. There are also many abbreviations you can use, the most useful probably being !$ for last argument and !! for last command (see “HISTORY EXPANSION” in the man page). However, these are often easily replaced with ctrl-r and alt-..
Go to your home directory with cd. Access files relative to your home directory with the ~ prefix (e.g. ~/.bashrc). In sh scripts refer to the home directory as $HOME.
To go back to the previous working directory: cd -.
If you are halfway through typing a command but change your mind, hit alt-# to add a # at the beginning and enter it as a comment (or use ctrl-a, #, enter). You can then return to it later via command history.
Use xargs (or parallel). It’s very powerful. Note you can control how many items execute per line (-L) as well as parallelism (-P). If you’re not sure if it’ll do the right thing, use xargs echo first. Also, -I{} is handy. Examples:

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      find . -name '*.py' | xargs grep some_function
      cat hosts | xargs -I{} ssh root@{} hostname

pstree -p is a helpful display of the process tree.
Use pgrep and pkill to find or signal processes by name (-f is helpful).
Know the various signals you can send processes. For example, to suspend a process, use kill -STOP [pid]. For the full list, see man 7 signal
Use nohup or disown if you want a background process to keep running forever.
Check what processes are listening via netstat -lntp or ss -plat (for TCP; add -u for UDP) or lsof -iTCP -sTCP:LISTEN -P -n (which also works on macOS).
See also lsof and fuser for open sockets and files.
See uptime or w to know how long the system has been running.
Use alias to create shortcuts for commonly used commands. For example, alias ll='ls -latr' creates a new alias ll.
Save aliases, shell settings, and functions you commonly use in ~/.bashrc, and arrange for login shells to source it. This will make your setup available in all your shell sessions.
Put the settings of environment variables as well as commands that should be executed when you login in ~/.bash_profile. Separate configuration will be needed for shells you launch from graphical environment logins and cron jobs.
Synchronize your configuration files (e.g. .bashrc and .bash_profile) among various computers with Git.
Understand that care is needed when variables and filenames include whitespace. Surround your Bash variables with quotes, e.g. "$FOO". Prefer the -0 or -print0 options to enable null characters to delimit filenames, e.g. locate -0 pattern | xargs -0 ls -al or find / -print0 -type d | xargs -0 ls -al. To iterate on filenames containing whitespace in a for loop, set your IFS to be a newline only using IFS=$'\n'.
In Bash scripts, use set -x (or the variant set -v, which logs raw input, including unexpanded variables and comments) for debugging output. Use strict modes unless you have a good reason not to: Use set -e to abort on errors (nonzero exit code). Use set -u to detect unset variable usages. Consider set -o pipefail too, to abort on errors within pipes (though read up on it more if you do, as this topic is a bit subtle). For more involved scripts, also use trap on EXIT or ERR. A useful habit is to start a script like this, which will make it detect and abort on common errors and print a message:

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      set -euo pipefail
      trap "echo 'error: Script failed: see failed command above'" ERR

In Bash scripts, subshells (written with parentheses) are convenient ways to group commands. A common example is to temporarily move to a different working directory, e.g.

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      # do something in current dir
      (cd /some/other/dir && other-command)
      # continue in original dir

In Bash, note there are lots of kinds of variable expansion. Checking a variable exists: ${name:?error message}. For example, if a Bash script requires a single argument, just write input_file=${1:?usage: $0 input_file}. Using a default value if a variable is empty: ${name:-default}. If you want to have an additional (optional) parameter added to the previous example, you can use something like output_file=${2:-logfile}. If $2 is omitted and thus empty, output_file will be set to logfile. Arithmetic expansion: i=$(( (i + 1) % 5 )). Sequences: {1..10}. Trimming of strings: ${var%suffix} and ${var#prefix}. For example if var=foo.pdf, then echo ${var%.pdf}.txt prints foo.txt.
Brace expansion using {…} can reduce having to re-type similar text and automate combinations of items. This is helpful in examples like mv foo.{txt,pdf} some-dir (which moves both files), cp somefile{,.bak} (which expands to cp somefile somefile.bak) or mkdir -p test-{a,b,c}/subtest-{1,2,3} (which expands all possible combinations and creates a directory tree). Brace expansion is performed before any other expansion.
The order of expansions is: brace expansion; tilde expansion, parameter and variable expansion, arithmetic expansion, and command substitution (done in a left-to-right fashion); word splitting; and filename expansion. (For example, a range like {1..20} cannot be expressed with variables using {$a..$b}. Use seq or a for loop instead, e.g., seq $a $b or for((i=a; i<=b; i++)); do ... ; done.)
The output of a command can be treated like a file via <(some command) (known as process substitution). For example, compare local /etc/hosts with a remote one:

`1`	`diff /etc/hosts <(ssh somehost cat /etc/hosts)`

When writing scripts you may want to put all of your code in curly braces. If the closing brace is missing, your script will be prevented from executing due to a syntax error. This makes sense when your script is going to be downloaded from the web, since it prevents partially downloaded scripts from executing:

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{
      # Your code here
}

A “here document” allows redirection of multiple lines of input as if from a file:

cat <<EOF
input
on multiple lines
EOF

In Bash, redirect both standard output and standard error via: some-command >logfile 2>&1 or some-command &>logfile. Often, to ensure a command does not leave an open file handle to standard input, tying it to the terminal you are in, it is also good practice to add </dev/null.
Use man ascii for a good ASCII table, with hex and decimal values. For general encoding info, man unicode, man utf-8, and man latin1 are helpful.
Use screen or tmux to multiplex the screen, especially useful on remote ssh sessions and to detach and re-attach to a session. byobu can enhance screen or tmux by providing more information and easier management. A more minimal alternative for session persistence only is dtach.
In ssh, knowing how to port tunnel with -L or -D (and occasionally -R) is useful, e.g. to access web sites from a remote server.
It can be useful to make a few optimizations to your ssh configuration; for example, this ~/.ssh/config contains settings to avoid dropped connections in certain network environments, uses compression (which is helpful with scp over low-bandwidth connections), and multiplex channels to the same server with a local control file:

      TCPKeepAlive=yes
      ServerAliveInterval=15
      ServerAliveCountMax=6
      Compression=yes
      ControlMaster auto
      ControlPath /tmp/%r@%h:%p
      ControlPersist yes

A few other options relevant to ssh are security sensitive and should be enabled with care, e.g. per subnet or host or in trusted networks: StrictHostKeyChecking=no, ForwardAgent=yes
Consider mosh an alternative to ssh that uses UDP, avoiding dropped connections and adding convenience on the road (requires server-side setup).
To get the permissions on a file in octal form, which is useful for system configuration but not available in ls and easy to bungle, use something like

`1`	`stat -c '%A %a %n' /etc/timezone`

For interactive selection of values from the output of another command, use percol or fzf.
For interaction with files based on the output of another command (like git), use fpp (PathPicker).
For a simple web server for all files in the current directory (and subdirs), available to anyone on your network, use: python -m SimpleHTTPServer 7777 (for port 7777 and Python 2) and python -m http.server 7777 (for port 7777 and Python 3).
For running a command as another user, use sudo. Defaults to running as root; use -u to specify another user. Use -i to login as that user (you will be asked for your password).
For switching the shell to another user, use su username or su - username. The latter with “-” gets an environment as if another user just logged in. Omitting the username defaults to root. You will be asked for the password of the user you are switching to.
Know about the 128K limit on command lines. This “Argument list too long” error is common when wildcard matching large numbers of files. (When this happens alternatives like find and xargs may help.)
For a basic calculator (and of course access to Python in general), use the python interpreter. For example,

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>>> 2+3
5

Processing files and data

To locate a file by name in the current directory, find . -iname '*something*' (or similar). To find a file anywhere by name, use locate something (but bear in mind updatedb may not have indexed recently created files).
For general searching through source or data files, there are several options more advanced or faster than grep -r, including (in rough order from older to newer) ack, ag (“the silver searcher”), and rg (ripgrep).
To convert HTML to text: lynx -dump -stdin
For Markdown, HTML, and all kinds of document conversion, try pandoc. For example, to convert a Markdown document to Word format: pandoc README.md --from markdown --to docx -o temp.docx
If you must handle XML, xmlstarlet is old but good.
For JSON, use jq. For interactive use, also see jid and jiq.
For YAML, use shyaml.
For Excel or CSV files, csvkit provides in2csv, csvcut, csvjoin, csvgrep, etc.
For Amazon S3, s3cmd is convenient and s4cmd is faster. Amazon’s aws and the improved saws are essential for other AWS-related tasks.
Know about sort and uniq, including uniq’s -u and -d options – see one-liners below. See also comm.
Know about cut, paste, and join to manipulate text files. Many people use cut but forget about join.
Know about wc to count newlines (-l), characters (-m), words (-w) and bytes (-c).
Know about tee to copy from stdin to a file and also to stdout, as in ls -al | tee file.txt.
For more complex calculations, including grouping, reversing fields, and statistical calculations, consider datamash.
Know that locale affects a lot of command line tools in subtle ways, including sorting order (collation) and performance. Most Linux installations will set LANG or other locale variables to a local setting like US English. But be aware sorting will change if you change locale. And know i18n routines can make sort or other commands run many times slower. In some situations (such as the set operations or uniqueness operations below) you can safely ignore slow i18n routines entirely and use traditional byte-based sort order, using export LC_ALL=C.
You can set a specific command’s environment by prefixing its invocation with the environment variable settings, as in TZ=Pacific/Fiji date.
Know basic awk and sed for simple data munging. See One-liners for examples.
To replace all occurrences of a string in place, in one or more files:

`1`	`perl -pi.bak -e 's/old-string/new-string/g' my-files-*.txt`

To rename multiple files and/or search and replace within files, try repren. (In some cases the rename command also allows multiple renames, but be careful as its functionality is not the same on all Linux distributions.)

      # Full rename of filenames, directories, and contents foo -> bar:
      repren --full --preserve-case --from foo --to bar .
      # Recover backup files whatever.bak -> whatever:
      repren --renames --from '(.*)\.bak' --to '\1' *.bak
      # Same as above, using rename, if available:
      rename 's/\.bak$//' *.bak

As the man page says, rsync really is a fast and extraordinarily versatile file copying tool. It’s known for synchronizing between machines but is equally useful locally. When security restrictions allow, using rsync instead of scp allows recovery of a transfer without restarting from scratch. It also is among the fastest ways to delete large numbers of files:

`1`	`mkdir empty && rsync -r --delete empty/ some-dir && rmdir some-dir`

For monitoring progress when processing files, use pv, pycp, pmonitor, progress, rsync --progress, or, for block-level copying, dd status=progress.
Use shuf to shuffle or select random lines from a file.
Know sort’s options. For numbers, use -n, or -h for handling human-readable numbers (e.g. from du -h). Know how keys work (-t and -k). In particular, watch out that you need to write -k1,1 to sort by only the first field; -k1 means sort according to the whole line. Stable sort (sort -s) can be useful. For example, to sort first by field 2, then secondarily by field 1, you can use sort -k1,1 | sort -s -k2,2.
If you ever need to write a tab literal in a command line in Bash (e.g. for the -t argument to sort), press ctrl-v [Tab] or write $'\t' (the latter is better as you can copy/paste it).
The standard tools for patching source code are diff and patch. See also diffstat for summary statistics of a diff and sdiff for a side-by-side diff. Note diff -r works for entire directories. Use diff -r tree1 tree2 | diffstat for a summary of changes. Use vimdiff to compare and edit files.
For binary files, use hd, hexdump or xxd for simple hex dumps and bvi, hexedit or biew for binary editing.
Also for binary files, strings (plus grep, etc.) lets you find bits of text.
For binary diffs (delta compression), use xdelta3.
To convert text encodings, try iconv. Or uconv for more advanced use; it supports some advanced Unicode things. For example:

      # Displays hex codes or actual names of characters (useful for debugging):
      uconv -f utf-8 -t utf-8 -x '::Any-Hex;' < input.txt
      uconv -f utf-8 -t utf-8 -x '::Any-Name;' < input.txt
      # Lowercase and removes all accents (by expanding and dropping them):
      uconv -f utf-8 -t utf-8 -x '::Any-Lower; ::Any-NFD; [:Nonspacing Mark:] >; ::Any-NFC;' < input.txt > output.txt

To split files into pieces, see split (to split by size) and csplit (to split by a pattern).
Date and time: To get the current date and time in the helpful ISO 8601 format, use date -u +"%Y-%m-%dT%H:%M:%SZ" (other options are problematic). To manipulate date and time expressions, use dateadd, datediff, strptime etc. from dateutils.
Use zless, zmore, zcat, and zgrep to operate on compressed files.
File attributes are settable via chattr and offer a lower-level alternative to file permissions. For example, to protect against accidental file deletion the immutable flag: sudo chattr +i /critical/directory/or/file
Use getfacl and setfacl to save and restore file permissions. For example:

1
2

   getfacl -R /some/path > permissions.txt
   setfacl --restore=permissions.txt

To create empty files quickly, use truncate (creates sparse file), fallocate (ext4, xfs, btrfs and ocfs2 filesystems), xfs_mkfile (almost any filesystems, comes in xfsprogs package), mkfile (for Unix-like systems like Solaris, Mac OS).

System debugging

For web debugging, curl and curl -I are handy, or their wget equivalents, or the more modern httpie.
To know current cpu/disk status, the classic tools are top (or the better htop), iostat, and iotop. Use iostat -mxz 15 for basic CPU and detailed per-partition disk stats and performance insight.
For network connection details, use netstat and ss.
For a quick overview of what’s happening on a system, dstat is especially useful. For broadest overview with details, use glances.
To know memory status, run and understand the output of free and vmstat. In particular, be aware the “cached” value is memory held by the Linux kernel as file cache, so effectively counts toward the “free” value.
Java system debugging is a different kettle of fish, but a simple trick on Oracle’s and some other JVMs is that you can run kill -3 <pid> and a full stack trace and heap summary (including generational garbage collection details, which can be highly informative) will be dumped to stderr/logs. The JDK’s jps, jstat, jstack, jmap are useful. SJK tools are more advanced.
Use mtr as a better traceroute, to identify network issues.
For looking at why a disk is full, ncdu saves time over the usual commands like du -sh *.
To find which socket or process is using bandwidth, try iftop or nethogs.
The ab tool (comes with Apache) is helpful for quick-and-dirty checking of web server performance. For more complex load testing, try siege.
For more serious network debugging, wireshark, tshark, or ngrep.
Know about strace and ltrace. These can be helpful if a program is failing, hanging, or crashing, and you don’t know why, or if you want to get a general idea of performance. Note the profiling option (-c), and the ability to attach to a running process (-p). Use trace child option (-f) to avoid missing important calls.
Know about ldd to check shared libraries etc — but never run it on untrusted files.
Know how to connect to a running process with gdb and get its stack traces.
Use /proc. It’s amazingly helpful sometimes when debugging live problems. Examples: /proc/cpuinfo, /proc/meminfo, /proc/cmdline, /proc/xxx/cwd, /proc/xxx/exe, /proc/xxx/fd/, /proc/xxx/smaps (where xxx is the process id or pid).
When debugging why something went wrong in the past, sar can be very helpful. It shows historic statistics on CPU, memory, network, etc.
For deeper systems and performance analyses, look at stap (SystemTap), perf, and sysdig.
Check what OS you’re on with uname or uname -a (general Unix/kernel info) or lsb_release -a (Linux distro info).
Use dmesg whenever something’s acting really funny (it could be hardware or driver issues).
If you delete a file and it doesn’t free up expected disk space as reported by du, check whether the file is in use by a process: lsof | grep deleted | grep "filename-of-my-big-file"

One-liners

A few examples of piecing together commands:

It is remarkably helpful sometimes that you can do set intersection, union, and difference of text files via sort/uniq. Suppose a and b are text files that are already uniqued. This is fast, and works on files of arbitrary size, up to many gigabytes. (Sort is not limited by memory, though you may need to use the -T option if /tmp is on a small root partition.) See also the note about LC_ALL above and sort’s -u option (left out for clarity below).

1
2
3

      sort a b | uniq > c   # c is a union b
      sort a b | uniq -d > c   # c is a intersect b
      sort a b b | uniq -u > c   # c is set difference a - b

Pretty-print two JSON files, normalizing their syntax, then coloring and paginating the result:

`1`	`diff <(jq --sort-keys . < file1.json) <(jq --sort-keys . < file2.json) \| colordiff \| less -R`

Use grep . * to quickly examine the contents of all files in a directory (so each line is paired with the filename), or head -100 * (so each file has a heading). This can be useful for directories filled with config settings like those in /sys, /proc, /etc.
Summing all numbers in the third column of a text file (this is probably 3X faster and 3X less code than equivalent Python):

`1`	`awk '{ x += $3 } END { print x }' myfile`

To see sizes/dates on a tree of files, this is like a recursive ls -l but is easier to read than ls -lR:

`1`	`find . -type f -ls`

Say you have a text file, like a web server log, and a certain value that appears on some lines, such as an acct_id parameter that is present in the URL. If you want a tally of how many requests for each acct_id:

`1`	`egrep -o 'acct_id=[0-9]+' access.log \| cut -d= -f2 \| sort \| uniq -c \| sort -rn`

To continuously monitor changes, use watch, e.g. check changes to files in a directory with watch -d -n 2 'ls -rtlh | tail' or to network settings while troubleshooting your wifi settings with watch -d -n 2 ifconfig.
Run this function to get a random tip from this document (parses Markdown and extracts an item):

      function taocl() {
        curl -s https://raw.githubusercontent.com/jlevy/the-art-of-command-line/master/README.md |
          sed '/cowsay[.]png/d' |
          pandoc -f markdown -t html |
          xmlstarlet fo --html --dropdtd |
          xmlstarlet sel -t -v "(html/body/ul/li[count(p)>0])[$RANDOM mod last()+1]" |
          xmlstarlet unesc | fmt -80 | iconv -t US
      }

Obscure but useful

expr: perform arithmetic or boolean operations or evaluate regular expressions
m4: simple macro processor
yes: print a string a lot
cal: nice calendar
env: run a command (useful in scripts)
printenv: print out environment variables (useful in debugging and scripts)
look: find English words (or lines in a file) beginning with a string
cut, paste and join: data manipulation
fmt: format text paragraphs
pr: format text into pages/columns
fold: wrap lines of text
column: format text fields into aligned, fixed-width columns or tables
expand and unexpand: convert between tabs and spaces
nl: add line numbers
seq: print numbers
bc: calculator
factor: factor integers
gpg: encrypt and sign files
toe: table of terminfo entries
nc: network debugging and data transfer
socat: socket relay and tcp port forwarder (similar to netcat)
slurm: network traffic visualization
dd: moving data between files or devices
file: identify type of a file
tree: display directories and subdirectories as a nesting tree; like ls but recursive
stat: file info
time: execute and time a command
timeout: execute a command for specified amount of time and stop the process when the specified amount of time completes.
lockfile: create semaphore file that can only be removed by rm -f
logrotate: rotate, compress and mail logs.
watch: run a command repeatedly, showing results and/or highlighting changes
when-changed: runs any command you specify whenever it sees file changed. See inotifywait and entr as well.
tac: print files in reverse
comm: compare sorted files line by line
strings: extract text from binary files
tr: character translation or manipulation
iconv or uconv: conversion for text encodings
split and csplit: splitting files
sponge: read all input before writing it, useful for reading from then writing to the same file, e.g., grep -v something some-file | sponge some-file
units: unit conversions and calculations; converts furlongs per fortnight to twips per blink (see also /usr/share/units/definitions.units)
apg: generates random passwords
xz: high-ratio file compression
ldd: dynamic library info
nm: symbols from object files
ab or wrk: benchmarking web servers
strace: system call debugging
mtr: better traceroute for network debugging
cssh: visual concurrent shell
rsync: sync files and folders over SSH or in local file system
wireshark and tshark: packet capture and network debugging
ngrep: grep for the network layer
host and dig: DNS lookups
lsof: process file descriptor and socket info
dstat: useful system stats
glances: high level, multi-subsystem overview
iostat: Disk usage stats
mpstat: CPU usage stats
vmstat: Memory usage stats
htop: improved version of top
last: login history
w: who’s logged on
id: user/group identity info
sar: historic system stats
iftop or nethogs: network utilization by socket or process
ss: socket statistics
dmesg: boot and system error messages
sysctl: view and configure Linux kernel parameters at run time
hdparm: SATA/ATA disk manipulation/performance
lsblk: list block devices: a tree view of your disks and disk partitions
lshw, lscpu, lspci, lsusb, dmidecode: hardware information, including CPU, BIOS, RAID, graphics, devices, etc.
lsmod and modinfo: List and show details of kernel modules.
fortune, ddate, and sl: um, well, it depends on whether you consider steam locomotives and Zippy quotations “useful”

macOS only

These are items relevant only on macOS.

Package management with brew (Homebrew) and/or port (MacPorts). These can be used to install on macOS many of the above commands.
Copy output of any command to a desktop app with pbcopy and paste input from one with pbpaste.
To enable the Option key in macOS Terminal as an alt key (such as used in the commands above like alt-b, alt-f, etc.), open Preferences -> Profiles -> Keyboard and select “Use Option as Meta key”.
To open a file with a desktop app, use open or open -a /Applications/Whatever.app.
Spotlight: Search files with mdfind and list metadata (such as photo EXIF info) with mdls.
Be aware macOS is based on BSD Unix, and many commands (for example ps, ls, tail, awk, sed) have many subtle variations from Linux, which is largely influenced by System V-style Unix and GNU tools. You can often tell the difference by noting a man page has the heading “BSD General Commands Manual.” In some cases GNU versions can be installed, too (such as gawk and gsed for GNU awk and sed). If writing cross-platform Bash scripts, avoid such commands (for example, consider Python or perl) or test carefully.
To get macOS release information, use sw_vers.

Windows only

These items are relevant only on Windows.

Ways to obtain Unix tools under Windows

Access the power of the Unix shell under Microsoft Windows by installing Cygwin. Most of the things described in this document will work out of the box.
On Windows 10, you can use Windows Subsystem for Linux (WSL), which provides a familiar Bash environment with Unix command line utilities.
If you mainly want to use GNU developer tools (such as GCC) on Windows, consider MinGW and its MSYS package, which provides utilities such as bash, gawk, make and grep. MSYS doesn’t have all the features compared to Cygwin. MinGW is particularly useful for creating native Windows ports of Unix tools.
Another option to get Unix look and feel under Windows is Cash. Note that only very few Unix commands and command-line options are available in this environment.

Useful Windows command-line tools

You can perform and script most Windows system administration tasks from the command line by learning and using wmic.
Native command-line Windows networking tools you may find useful include ping, ipconfig, tracert, and netstat.
You can perform many useful Windows tasks by invoking the Rundll32 command.

Cygwin tips and tricks

Install additional Unix programs with the Cygwin’s package manager.
Use mintty as your command-line window.
Access the Windows clipboard through /dev/clipboard.
Run cygstart to open an arbitrary file through its registered application.
Access the Windows registry with regtool.
Note that a C:\ Windows drive path becomes /cygdrive/c under Cygwin, and that Cygwin’s / appears under C:\cygwin on Windows. Convert between Cygwin and Windows-style file paths with cygpath. This is most useful in scripts that invoke Windows programs.

More resources

awesome-shell: A curated list of shell tools and resources.
awesome-osx-command-line: A more in-depth guide for the macOS command line.
Strict mode for writing better shell scripts.
shellcheck: A shell script static analysis tool. Essentially, lint for bash/sh/zsh.
Filenames and Pathnames in Shell: The sadly complex minutiae on how to handle filenames correctly in shell scripts.
Data Science at the Command Line: More commands and tools helpful for doing data science, from the book of the same name

Disclaimer

With the exception of very small tasks, code is written so others can read it. With power comes responsibility. The fact you can do something in Bash doesn’t necessarily mean you should! ;)

License

This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.

tldr

Thu, 31 Jul 2025 15:34:46 +0800

tldr-pages/tldr

What is tldr-pages?

The tldr-pages project is a collection of community-maintained help pages for command-line tools, that aims to be a simpler, more approachable complement to traditional man pages.

Maybe you’re new to the command-line world. Perhaps you’re just a little rusty or can’t always recall the arguments for commands like lsof, or tar?

It certainly doesn’t help that, in the past, the first option explained in man tar was:

$ man tar
...
-b blocksize
   Specify the block size, in 512-byte records, for tape drive I/O.
   As a rule, this argument is only needed when reading from or writing to tape drives,
   and usually not even then as the default block size of 20 records (10240 bytes) is very common.
...

There is room for simpler help pages focused on practical examples. How about:

This repository is just that: an ever-growing collection of examples for the most common UNIX, Linux, macOS, FreeBSD, NetBSD, OpenBSD, SunOS, Android, Windows, and Cisco IOS command-line tools.

How do I use it?

[!TIP] For browsing without installing a client on your computer, see the web client at https://tldr.inbrowser.app (with offline support using PWA).

A popular and convenient way to access these pages on your computer is to install the official Python client, which can be installed via pip3 (or other package managers):

`1`	`pip3 install tldr`

Linux and Mac users can also install the official Rust Client using Homebrew (or other package managers on other operating systems):

`1`	`brew install tlrc`

Alternatively, you can also use the official Node.js client, although it has fallen behind in updates:

`1`	`npm install -g tldr`

Then you have direct access to simplified, easy-to-read help for commands, such as tar, accessible through typing tldr tar instead of the standard man tar.

If you don’t want to install any software, check out the PDF version instead.

[!NOTE] PDFs for translations are available for most languages. You can find them in the release assets of the latest release.

There are also various other clients provided by the community, both for the command-line and for other platforms. For a comprehensive list of clients, head over to our Wiki.

How do I contribute to tldr-pages?

All contributions are welcome!

Some ways to contribute include:

Adding your favorite command that isn’t covered.
Adding examples or improving the content of an existing page.
Adding requested pages from our issues with the help wanted label.
Translating pages into different languages.

All tldr pages are written in Markdown so that they can be edited quite easily and changes can be submitted in pull requests here using Git on the command-line or using the GitHub web interface.

We strive to maintain a welcoming and collaborative community. If it’s your first time contributing, have a look at the contributing guidelines, and go ahead!

If you’d like to contribute to translations, you can visit https://lukwebsforge.github.io/tldri18n/ to see the overall progress of all translations, and which translations are missing or outdated.

You are also welcome to join us on the matrix chatroom!

Similar projects

Command Line Interface Pages allows you to write standardized help pages for CLI, directories, and configs.
Cheat allows you to create and view interactive cheatsheets on the command-line. It was designed to help remind Unix system administrators of options for commands that they use frequently, but not frequently enough to remember.
cheat.sh Aggregates cheat sheets from multiple sources (including tldr-pages) into 1 unified interface.
devhints Rico’s cheatsheets are not just focused on the command-line and include a plethora of other cheatsheets related to programming.
eg provides detailed examples with explanations on the command-line. Examples come from the repository, but eg supports displaying custom examples and commands alongside the defaults.
kb is a minimalist command-line knowledge base manager. kb can be used to organize your notes and cheatsheets in a minimalist and clean way. It also supports non-text files.
navi is an interactive cheatsheet tool, which allows you to browse through specific examples or complete commands on the fly.
bropages (deprecated) are a highly readable supplement to man pages. It shows concise, common-case examples for Unix commands. The examples are submitted by the user base, and can be voted up or down; the best entries are what people see first when they look up a command.

What does “tldr” mean?

TL;DR stands for “Too Long; Didn’t Read”. It originated as Internet slang, where it is used to indicate that a long text (or parts of it) has been skipped as too lengthy. Read more in How-To Geek’s article.

OCRmyPDF

Sun, 13 Jul 2025 15:31:01 +0800

ocrmypdf/OCRmyPDF

OCRmyPDF adds an OCR text layer to scanned PDF files, allowing them to be searched or copy-pasted.

ocrmypdf                      # it's a scriptable command line program
   -l eng+fra                 # it supports multiple languages
   --rotate-pages             # it can fix pages that are misrotated
   --deskew                   # it can deskew crooked PDFs!
   --title "My PDF"           # it can change output metadata
   --jobs 4                   # it uses multiple cores by default
   --output-type pdfa         # it produces PDF/A by default
   input_scanned.pdf          # takes PDF input (or images)
   output_searchable.pdf      # produces validated PDF output

See the release notes for details on the latest changes.

Main features

Generates a searchable PDF/A file from a regular PDF
Places OCR text accurately below the image to ease copy / paste
Keeps the exact resolution of the original embedded images
When possible, inserts OCR information as a “lossless” operation without disrupting any other content
Optimizes PDF images, often producing files smaller than the input file
If requested, deskews and/or cleans the image before performing OCR
Validates input and output files
Distributes work across all available CPU cores
Uses Tesseract OCR engine to recognize more than 100 languages
Keeps your private data private.
Scales properly to handle files with thousands of pages.
Battle-tested on millions of PDFs.

For details: please consult the documentation.

Motivation

I searched the web for a free command line tool to OCR PDF files: I found many, but none of them were really satisfying:

Either they produced PDF files with misplaced text under the image (making copy/paste impossible)
Or they did not handle accents and multilingual characters
Or they changed the resolution of the embedded images
Or they generated ridiculously large PDF files
Or they crashed when trying to OCR
Or they did not produce valid PDF files
On top of that none of them produced PDF/A files (format dedicated for long time storage)

…so I decided to develop my own tool.

Installation

Linux, Windows, macOS and FreeBSD are supported. Docker images are also available, for both x64 and ARM.

Operating system	Install command
Debian, Ubuntu	`apt install ocrmypdf`
Windows Subsystem for Linux	`apt install ocrmypdf`
Fedora	`dnf install ocrmypdf`
macOS (Homebrew)	`brew install ocrmypdf`
macOS (MacPorts)	`port install ocrmypdf`
macOS (nix)	`nix-env -i ocrmypdf`
LinuxBrew	`brew install ocrmypdf`
FreeBSD	`pkg install py-ocrmypdf`
Ubuntu Snap	`snap install ocrmypdf`

For everyone else, see our documentation for installation steps.

Languages

OCRmyPDF uses Tesseract for OCR, and relies on its language packs. For Linux users, you can often find packages that provide language packs:

# Display a list of all Tesseract language packs
apt-cache search tesseract-ocr

# Debian/Ubuntu users
apt-get install tesseract-ocr-chi-sim  # Example: Install Chinese Simplified language pack

# Arch Linux users
pacman -S tesseract-data-eng tesseract-data-deu # Example: Install the English and German language packs

# brew macOS users
brew install tesseract-lang

You can then pass the -l LANG argument to OCRmyPDF to give a hint as to what languages it should search for. Multiple languages can be requested.

OCRmyPDF supports Tesseract 4.1.1+. It will automatically use whichever version it finds first on the PATH environment variable. On Windows, if PATH does not provide a Tesseract binary, we use the highest version number that is installed according to the Windows Registry.

Documentation and support

Once OCRmyPDF is installed, the built-in help which explains the command syntax and options can be accessed via:

`1`	`ocrmypdf --help`

Our documentation is served on Read the Docs.

Please report issues on our GitHub issues page, and follow the issue template for quick response.

Feature demo

# Add an OCR layer and convert to PDF/A
ocrmypdf input.pdf output.pdf

# Convert an image to single page PDF
ocrmypdf input.jpg output.pdf

# Add OCR to a file in place (only modifies file on success)
ocrmypdf myfile.pdf myfile.pdf

# OCR with non-English languages (look up your language's ISO 639-3 code)
ocrmypdf -l fra LeParisien.pdf LeParisien.pdf

# OCR multilingual documents
ocrmypdf -l eng+fra Bilingual-English-French.pdf Bilingual-English-French.pdf

# Deskew (straighten crooked pages)
ocrmypdf --deskew input.pdf output.pdf

For more features, see the documentation.

Requirements

In addition to the required Python version, OCRmyPDF requires external program installations of Ghostscript and Tesseract OCR. OCRmyPDF is pure Python, and runs on pretty much everything: Linux, macOS, Windows and FreeBSD.

Press & Media

Going paperless with OCRmyPDF
Converting a scanned document into a compressed searchable PDF with redactions
c’t 1-2014, page 59: Detailed presentation of OCRmyPDF v1.0 in the leading German IT magazine c’t
heise Open Source, 09/2014: Texterkennung mit OCRmyPDF
heise Durchsuchbare PDF-Dokumente mit OCRmyPDF erstellen
Excellent Utilities: OCRmyPDF
LinuxUser Texterkennung mit OCRmyPDF und Scanbd automatisieren
Y Combinator discussion

Business enquiries

OCRmyPDF would not be the software that it is today without companies and users choosing to provide support for feature development and consulting enquiries. We are happy to discuss all enquiries, whether for extending the existing feature set, or integrating OCRmyPDF into a larger system.

License

The OCRmyPDF software is licensed under the Mozilla Public License 2.0 (MPL-2.0). This license permits integration of OCRmyPDF with other code, included commercial and closed source, but asks you to publish source-level modifications you make to OCRmyPDF.

Some components of OCRmyPDF have other licenses, as indicated by standard SPDX license identifiers or the DEP5 copyright and licensing information file. Generally speaking, non-core code is licensed under MIT, and the documentation and test files are licensed under Creative Commons ShareAlike 4.0 (CC-BY-SA 4.0).

Disclaimer

The software is distributed on an “AS IS” BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

fzf

Thu, 10 Jul 2025 15:32:18 +0800

junegunn/fzf

^{Special thanks to:}

Warp, the intelligent terminal for developers

Available for MacOS, Linux, & Windows

fzf is a general-purpose command-line fuzzy finder.

It’s an interactive filter program for any kind of list; files, command history, processes, hostnames, bookmarks, git commits, etc. It implements a “fuzzy” matching algorithm, so you can quickly type in patterns with omitted characters and still get the results you want.

Highlights

📦 Portable — Distributed as a single binary for easy installation
⚡ Blazingly fast — Highly optimized code instantly processes millions of items
🛠️ Extremely versatile — Fully customizable via an event-action binding mechanism
🔋 Batteries included — Includes integration with bash, zsh, fish, Vim, and Neovim

Installation

Using Homebrew

You can use Homebrew (on macOS or Linux) to install fzf.

`1`	`brew install fzf`

[!IMPORTANT] To set up shell integration (key bindings and fuzzy completion), see the instructions below.

fzf is also available via MacPorts: sudo port install fzf

Linux packages

Package Manager	Linux Distribution	Command
APK	Alpine Linux	`sudo apk add fzf`
APT	Debian 9+/Ubuntu 19.10+	`sudo apt install fzf`
Conda		`conda install -c conda-forge fzf`
DNF	Fedora	`sudo dnf install fzf`
Nix	NixOS, etc.	`nix-env -iA nixpkgs.fzf`
Pacman	Arch Linux	`sudo pacman -S fzf`
pkg	FreeBSD	`pkg install fzf`
pkgin	NetBSD	`pkgin install fzf`
pkg_add	OpenBSD	`pkg_add fzf`
Portage	Gentoo	`emerge --ask app-shells/fzf`
Spack		`spack install fzf`
XBPS	Void Linux	`sudo xbps-install -S fzf`
Zypper	openSUSE	`sudo zypper install fzf`

[!IMPORTANT] To set up shell integration (key bindings and fuzzy completion), see the instructions below.

Windows packages

On Windows, fzf is available via Chocolatey, Scoop, Winget, and MSYS2:

Package manager	Command
Chocolatey	`choco install fzf`
Scoop	`scoop install fzf`
Winget	`winget install fzf`
MSYS2 (pacman)	`pacman -S $MINGW_PACKAGE_PREFIX-fzf`

Using git

Alternatively, you can “git clone” this repository to any directory and run install script.

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git clone --depth 1 https://github.com/junegunn/fzf.git ~/.fzf
~/.fzf/install

The install script will add lines to your shell configuration file to modify $PATH and set up shell integration.

Binary releases

You can download the official fzf binaries from the releases page.

https://github.com/junegunn/fzf/releases

Setting up shell integration

Add the following line to your shell configuration file.

bash

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# Set up fzf key bindings and fuzzy completion
eval "$(fzf --bash)"

zsh

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# Set up fzf key bindings and fuzzy completion
source <(fzf --zsh)

fish

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# Set up fzf key bindings
fzf --fish | source

[!NOTE] --bash, --zsh, and --fish options are only available in fzf 0.48.0 or later. If you have an older version of fzf, or want finer control, you can source individual script files in the /shell directory. The location of the files may vary depending on the package manager you use. Please refer to the package documentation for more information. (e.g. apt show fzf)

[!TIP] You can disable CTRL-T or ALT-C binding by setting FZF_CTRL_T_COMMAND or FZF_ALT_C_COMMAND to an empty string when sourcing the script. For example, to disable ALT-C binding:

bash: FZF_ALT_C_COMMAND= eval "$(fzf --bash)"

zsh: FZF_ALT_C_COMMAND= source <(fzf --zsh)

fish: fzf --fish | FZF_ALT_C_COMMAND= source

Setting the variables after sourcing the script will have no effect.

Vim/Neovim plugin

If you use vim-plug, add this to your Vim configuration file:

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Plug 'junegunn/fzf', { 'do': { -> fzf#install() } }
Plug 'junegunn/fzf.vim'

junegunn/fzf provides the basic library functions
- fzf#install() makes sure that you have the latest binary
junegunn/fzf.vim is a separate project that provides a variety of useful commands

To learn more about the Vim integration, see README-VIM.md.

[!TIP] If you use Neovim and prefer Lua-based plugins, check out fzf-lua.

Upgrading fzf

fzf is being actively developed, and you might want to upgrade it once in a while. Please follow the instruction below depending on the installation method used.

git: cd ~/.fzf && git pull && ./install
brew: brew update; brew upgrade fzf
macports: sudo port upgrade fzf
chocolatey: choco upgrade fzf
vim-plug: :PlugUpdate fzf

Building fzf

See BUILD.md.

Usage

fzf will launch interactive finder, read the list from STDIN, and write the selected item to STDOUT.

`1`	`find * -type f \| fzf > selected`

Without STDIN pipe, fzf will traverse the file system under the current directory to get the list of files.

`1`	`vim $(fzf)`

[!NOTE] You can override the default behavior

Either by setting $FZF_DEFAULT_COMMAND to a command that generates the desired list

Or by setting --walker, --walker-root, and --walker-skip options in $FZF_DEFAULT_OPTS

[!WARNING] A more robust solution would be to use xargs but we’ve presented the above as it’s easier to grasp
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fzf --print0 | xargs -0 -o vim

[!TIP] fzf also has the ability to turn itself into a different process.
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fzf --bind 'enter:become(vim {})'
See Turning into a different process for more information.

Using the finder

CTRL-K / CTRL-J (or CTRL-P / CTRL-N) to move cursor up and down
Enter key to select the item, CTRL-C / CTRL-G / ESC to exit
On multi-select mode (-m), TAB and Shift-TAB to mark multiple items
Emacs style key bindings
Mouse: scroll, click, double-click; shift-click and shift-scroll on multi-select mode

Display modes

fzf by default runs in fullscreen mode, but there are other display modes.

`--height` mode

With --height HEIGHT[%], fzf will start below the cursor with the given height.

`1`	`fzf --height 40%`

reverse layout and --border goes well with this option.

`1`	`fzf --height 40% --layout reverse --border`

By prepending ~ to the height, you’re setting the maximum height.

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# Will take as few lines as possible to display the list
seq 3 | fzf --height ~100%
seq 3000 | fzf --height ~100%

Height value can be a negative number.

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# Screen height - 3
fzf --height -3

`--tmux` mode

With --tmux option, fzf will start in a tmux popup.

# --tmux [center|top|bottom|left|right][,SIZE[%]][,SIZE[%][,border-native]]

fzf --tmux center         # Center, 50% width and height
fzf --tmux 80%            # Center, 80% width and height
fzf --tmux 100%,50%       # Center, 100% width and 50% height
fzf --tmux left,40%       # Left, 40% width
fzf --tmux left,40%,90%   # Left, 40% width, 90% height
fzf --tmux top,40%        # Top, 40% height
fzf --tmux bottom,80%,40% # Bottom, 80% height, 40% height

--tmux is silently ignored when you’re not on tmux.

[!NOTE] If you’re stuck with an old version of tmux that doesn’t support popup, or if you want to open fzf in a regular tmux pane, check out fzf-tmux script.

[!TIP] You can add these options to $FZF_DEFAULT_OPTS so that they’re applied by default. For example,
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# Open in tmux popup if on tmux, otherwise use --height mode
export FZF_DEFAULT_OPTS='--height 40% --tmux bottom,40% --layout reverse --border top'

Search syntax

Unless otherwise specified, fzf starts in “extended-search mode” where you can type in multiple search terms delimited by spaces. e.g. ^music .mp3$ sbtrkt !fire

Token	Match type	Description
`sbtrkt`	fuzzy-match	Items that match `sbtrkt`
`'wild`	exact-match (quoted)	Items that include `wild`
`'wild'`	exact-boundary-match (quoted both ends)	Items that include `wild` at word boundaries
`^music`	prefix-exact-match	Items that start with `music`
`.mp3$`	suffix-exact-match	Items that end with `.mp3`
`!fire`	inverse-exact-match	Items that do not include `fire`
`!^music`	inverse-prefix-exact-match	Items that do not start with `music`
`!.mp3$`	inverse-suffix-exact-match	Items that do not end with `.mp3`

If you don’t prefer fuzzy matching and do not wish to “quote” every word, start fzf with -e or --exact option. Note that when --exact is set, '-prefix “unquotes” the term.

A single bar character term acts as an OR operator. For example, the following query matches entries that start with core and end with either go, rb, or py.

`1`	`^core go$ \| rb$ \| py$`

Environment variables

FZF_DEFAULT_COMMAND
- Default command to use when input is tty
- e.g. export FZF_DEFAULT_COMMAND='fd --type f'
FZF_DEFAULT_OPTS
- Default options
- e.g. export FZF_DEFAULT_OPTS="--layout=reverse --inline-info"
FZF_DEFAULT_OPTS_FILE
- If you prefer to manage default options in a file, set this variable to point to the location of the file
- e.g. export FZF_DEFAULT_OPTS_FILE=~/.fzfrc

[!WARNING] FZF_DEFAULT_COMMAND is not used by shell integration due to the slight difference in requirements.

CTRL-T runs $FZF_CTRL_T_COMMAND to get a list of files and directories

ALT-C runs $FZF_ALT_C_COMMAND to get a list of directories

vim ~/**<tab> runs fzf_compgen_path() with the prefix (~/) as the first argument

cd foo**<tab> runs fzf_compgen_dir() with the prefix (foo) as the first argument

The available options are described later in this document.

Customizing the look

The user interface of fzf is fully customizable with a large number of configuration options. For a quick setup, you can start with one of the style presets — default, full, or minimal — using the --style option.

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fzf --style full \
    --preview 'fzf-preview.sh {}' --bind 'focus:transform-header:file --brief {}'

Preset	Screenshot
`default`
`full`
`minimal`

Here’s an example based on the full preset:

git ls-files | fzf --style full \
    --border --padding 1,2 \
    --border-label ' Demo ' --input-label ' Input ' --header-label ' File Type ' \
    --preview 'fzf-preview.sh {}' \
    --bind 'result:transform-list-label:
        if [[ -z $FZF_QUERY ]]; then
          echo " $FZF_MATCH_COUNT items "
        else
          echo " $FZF_MATCH_COUNT matches for [$FZF_QUERY] "
        fi
        ' \
    --bind 'focus:transform-preview-label:[[ -n {} ]] && printf " Previewing [%s] " {}' \
    --bind 'focus:+transform-header:file --brief {} || echo "No file selected"' \
    --bind 'ctrl-r:change-list-label( Reloading the list )+reload(sleep 2; git ls-files)' \
    --color 'border:#aaaaaa,label:#cccccc' \
    --color 'preview-border:#9999cc,preview-label:#ccccff' \
    --color 'list-border:#669966,list-label:#99cc99' \
    --color 'input-border:#996666,input-label:#ffcccc' \
    --color 'header-border:#6699cc,header-label:#99ccff'

Options

See the man page (fzf --man or man fzf) for the full list of options.

Demo

If you learn by watching videos, check out this screencast by @samoshkin to explore fzf features.

Examples

Wiki page of examples
- Disclaimer: The examples on this page are maintained by the community and are not thoroughly tested
Advanced fzf examples

Key bindings for command-line

By setting up shell integration, you can use the following key bindings in bash, zsh, and fish.

CTRL-T - Paste the selected files and directories onto the command-line

The list is generated using --walker file,dir,follow,hidden option
- You can override the behavior by setting FZF_CTRL_T_COMMAND to a custom command that generates the desired list
- Or you can set --walker* options in FZF_CTRL_T_OPTS

Set FZF_CTRL_T_OPTS to pass additional options to fzf

# Preview file content using bat (https://github.com/sharkdp/bat)
export FZF_CTRL_T_OPTS="
  --walker-skip .git,node_modules,target
  --preview 'bat -n --color=always {}'
  --bind 'ctrl-/:change-preview-window(down|hidden|)'"

Can be disabled by setting FZF_CTRL_T_COMMAND to an empty string when sourcing the script

CTRL-R - Paste the selected command from history onto the command-line

If you want to see the commands in chronological order, press CTRL-R again which toggles sorting by relevance
Press CTRL-/ or ALT-/ to toggle line wrapping

Set FZF_CTRL_R_OPTS to pass additional options to fzf

# CTRL-Y to copy the command into clipboard using pbcopy
export FZF_CTRL_R_OPTS="
  --bind 'ctrl-y:execute-silent(echo -n {2..} | pbcopy)+abort'
  --color header:italic
  --header 'Press CTRL-Y to copy command into clipboard'"

ALT-C - cd into the selected directory
- The list is generated using --walker dir,follow,hidden option
- Set FZF_ALT_C_COMMAND to override the default command
  - Or you can set --walker-* options in FZF_ALT_C_OPTS
- Set FZF_ALT_C_OPTS to pass additional options to fzf
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  # Print tree structure in the preview window export FZF_ALT_C_OPTS=" --walker-skip .git,node_modules,target --preview 'tree -C {}'"
- Can be disabled by setting FZF_ALT_C_COMMAND to an empty string when sourcing the script

Display modes for these bindings can be separately configured via FZF_{CTRL_T,CTRL_R,ALT_C}_OPTS or globally via FZF_DEFAULT_OPTS. (e.g. FZF_CTRL_R_OPTS='--tmux bottom,60% --height 60% --border top')

More tips can be found on the wiki page.

Fuzzy completion for bash and zsh

Files and directories

Fuzzy completion for files and directories can be triggered if the word before the cursor ends with the trigger sequence, which is by default **.

COMMAND [DIRECTORY/][FUZZY_PATTERN]**<TAB>

# Files under the current directory
# - You can select multiple items with TAB key
vim **<TAB>

# Files under parent directory
vim ../**<TAB>

# Files under parent directory that match `fzf`
vim ../fzf**<TAB>

# Files under your home directory
vim ~/**<TAB>


# Directories under current directory (single-selection)
cd **<TAB>

# Directories under ~/github that match `fzf`
cd ~/github/fzf**<TAB>

Process IDs

Fuzzy completion for PIDs is provided for kill command.

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# Can select multiple processes with <TAB> or <Shift-TAB> keys
kill -9 **<TAB>

Host names

For ssh and telnet commands, fuzzy completion for hostnames is provided. The names are extracted from /etc/hosts and ~/.ssh/config.

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ssh **<TAB>
telnet **<TAB>

Environment variables / Aliases

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unset **<TAB>
export **<TAB>
unalias **<TAB>

Customizing fzf options for completion

# Use ~~ as the trigger sequence instead of the default **
export FZF_COMPLETION_TRIGGER='~~'

# Options to fzf command
export FZF_COMPLETION_OPTS='--border --info=inline'

# Options for path completion (e.g. vim **<TAB>)
export FZF_COMPLETION_PATH_OPTS='--walker file,dir,follow,hidden'

# Options for directory completion (e.g. cd **<TAB>)
export FZF_COMPLETION_DIR_OPTS='--walker dir,follow'

# Advanced customization of fzf options via _fzf_comprun function
# - The first argument to the function is the name of the command.
# - You should make sure to pass the rest of the arguments ($@) to fzf.
_fzf_comprun() {
  local command=$1
  shift

  case "$command" in
    cd)           fzf --preview 'tree -C {} | head -200'   "$@" ;;
    export|unset) fzf --preview "eval 'echo \$'{}"         "$@" ;;
    ssh)          fzf --preview 'dig {}'                   "$@" ;;
    *)            fzf --preview 'bat -n --color=always {}' "$@" ;;
  esac
}

Customizing completion source for paths and directories

# Use fd (https://github.com/sharkdp/fd) for listing path candidates.
# - The first argument to the function ($1) is the base path to start traversal
# - See the source code (completion.{bash,zsh}) for the details.
_fzf_compgen_path() {
  fd --hidden --follow --exclude ".git" . "$1"
}

# Use fd to generate the list for directory completion
_fzf_compgen_dir() {
  fd --type d --hidden --follow --exclude ".git" . "$1"
}

Supported commands

On bash, fuzzy completion is enabled only for a predefined set of commands (complete | grep _fzf to see the list). But you can enable it for other commands as well by using _fzf_setup_completion helper function.

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# usage: _fzf_setup_completion path|dir|var|alias|host COMMANDS...
_fzf_setup_completion path ag git kubectl
_fzf_setup_completion dir tree

Custom fuzzy completion

(Custom completion API is experimental and subject to change)

For a command named “COMMAND”, define _fzf_complete_COMMAND function using _fzf_complete helper.

# Custom fuzzy completion for "doge" command
#   e.g. doge **<TAB>
_fzf_complete_doge() {
  _fzf_complete --multi --reverse --prompt="doge> " -- "$@" < <(
    echo very
    echo wow
    echo such
    echo doge
  )
}

The arguments before -- are the options to fzf.
After --, simply pass the original completion arguments unchanged ("$@").
Then, write a set of commands that generates the completion candidates and feed its output to the function using process substitution (< <(...)).

zsh will automatically pick up the function using the naming convention but in bash you have to manually associate the function with the command using the complete command.

`1`	`[ -n "$BASH" ] && complete -F _fzf_complete_doge -o default -o bashdefault doge`

If you need to post-process the output from fzf, define _fzf_complete_COMMAND_post as follows.

_fzf_complete_foo() {
  _fzf_complete --multi --reverse --header-lines=3 -- "$@" < <(
    ls -al
  )
}

_fzf_complete_foo_post() {
  awk '{print $NF}'
}

[ -n "$BASH" ] && complete -F _fzf_complete_foo -o default -o bashdefault foo

Vim plugin

See README-VIM.md.

Advanced topics

Customizing for different types of input

Since fzf is a general-purpose text filter, its algorithm was designed to “generally” work well with any kind of input. However, admittedly, there is no true one-size-fits-all solution, and you may want to tweak the algorithm and some of the settings depending on the type of the input. To make this process easier, fzf provides a set of “scheme"s for some common input types.

Scheme	Description
`--scheme=default`	Generic scheme designed to work well with any kind of input
`--scheme=path`	Suitable for file paths
`--scheme=history`	Suitable for command history or any input where chronological ordering is important

(See fzf --man for the details)

Performance

fzf is fast. Performance should not be a problem in most use cases. However, you might want to be aware of the options that can affect performance.

--ansi tells fzf to extract and parse ANSI color codes in the input, and it makes the initial scanning slower. So it’s not recommended that you add it to your $FZF_DEFAULT_OPTS.
--nth makes fzf slower because it has to tokenize each line.
A plain string --delimiter should be preferred over a regular expression delimiter.
--with-nth makes fzf slower as fzf has to tokenize and reassemble each line.

Executing external programs

You can set up key bindings for starting external processes without leaving fzf (execute, execute-silent).

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# Press F1 to open the file with less without leaving fzf
# Press CTRL-Y to copy the line to clipboard and aborts fzf (requires pbcopy)
fzf --bind 'f1:execute(less -f {}),ctrl-y:execute-silent(echo {} | pbcopy)+abort'

See KEY/EVENT BINDINGS section of the man page for details.

Turning into a different process

become(...) is similar to execute(...)/execute-silent(...) described above, but instead of executing the command and coming back to fzf on complete, it turns fzf into a new process for the command.

`1`	`fzf --bind 'enter:become(vim {})'`

Compared to the seemingly equivalent command substitution vim "$(fzf)", this approach has several advantages:

Vim will not open an empty file when you terminate fzf with CTRL-C
Vim will not open an empty file when you press ENTER on an empty result
Can handle multiple selections even when they have whitespaces
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fzf --multi --bind 'enter:become(vim {+})'

To be fair, running fzf --print0 | xargs -0 -o vim instead of vim "$(fzf)" resolves all of the issues mentioned. Nonetheless, become(...) still offers additional benefits in different scenarios.

You can set up multiple bindings to handle the result in different ways without any wrapping script
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fzf --bind 'enter:become(vim {}),ctrl-e:become(emacs {})'
- Previously, you would have to use --expect=ctrl-e and check the first line of the output of fzf

You can easily build the subsequent command using the field index expressions of fzf

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# Open the file in Vim and go to the line
git grep --line-number . |
    fzf --delimiter : --nth 3.. --bind 'enter:become(vim {1} +{2})'

Reloading the candidate list

By binding reload action to a key or an event, you can make fzf dynamically reload the candidate list. See https://github.com/junegunn/fzf/issues/1750 for more details.

1. Update the list of processes by pressing CTRL-R

ps -ef |
  fzf --bind 'ctrl-r:reload(ps -ef)' \
      --header 'Press CTRL-R to reload' --header-lines=1 \
      --height=50% --layout=reverse

2. Switch between sources by pressing CTRL-D or CTRL-F

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FZF_DEFAULT_COMMAND='find . -type f' \
  fzf --bind 'ctrl-d:reload(find . -type d),ctrl-f:reload(eval "$FZF_DEFAULT_COMMAND")' \
      --height=50% --layout=reverse

3. Interactive ripgrep integration

The following example uses fzf as the selector interface for ripgrep. We bound reload action to change event, so every time you type on fzf, the ripgrep process will restart with the updated query string denoted by the placeholder expression {q}. Also, note that we used --disabled option so that fzf doesn’t perform any secondary filtering.

: | rg_prefix='rg --column --line-number --no-heading --color=always --smart-case' \
    fzf --bind 'start:reload:$rg_prefix ""' \
        --bind 'change:reload:$rg_prefix {q} || true' \
        --bind 'enter:become(vim {1} +{2})' \
        --ansi --disabled \
        --height=50% --layout=reverse

If ripgrep doesn’t find any matches, it will exit with a non-zero exit status, and fzf will warn you about it. To suppress the warning message, we added || true to the command, so that it always exits with 0.

See “Using fzf as interactive Ripgrep launcher” for more sophisticated examples.

Preview window

When the --preview option is set, fzf automatically starts an external process with the current line as the argument and shows the result in the split window. Your $SHELL is used to execute the command with $SHELL -c COMMAND. The window can be scrolled using the mouse or custom key bindings.

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# {} is replaced with the single-quoted string of the focused line
fzf --preview 'cat {}'

Preview window supports ANSI colors, so you can use any program that syntax-highlights the content of a file, such as Bat or Highlight:

`1`	`fzf --preview 'bat --color=always {}' --preview-window '~3'`

You can customize the size, position, and border of the preview window using --preview-window option, and the foreground and background color of it with --color option. For example,

fzf --height 40% --layout reverse --info inline --border \
    --preview 'file {}' --preview-window up,1,border-horizontal \
    --bind 'ctrl-/:change-preview-window(50%|hidden|)' \
    --color 'fg:#bbccdd,fg+:#ddeeff,bg:#334455,preview-bg:#223344,border:#778899'

See the man page (man fzf) for the full list of options.

More advanced examples can be found here.

[!WARNING] Since fzf is a general-purpose text filter rather than a file finder, it is not a good idea to add --preview option to your $FZF_DEFAULT_OPTS.

# *********************
# ** DO NOT DO THIS! **
# *********************
export FZF_DEFAULT_OPTS='--preview "bat --style=numbers --color=always --line-range :500 {}"'

# bat doesn't work with any input other than the list of files
ps -ef | fzf
seq 100 | fzf
history | fzf

Previewing an image

fzf can display images in the preview window using one of the following protocols:

See bin/fzf-preview.sh script for more information.

`1`	`fzf --preview 'fzf-preview.sh {}'`

Tips

Respecting `.gitignore`

You can use fd, ripgrep, or the silver searcher to traverse the file system while respecting .gitignore.

# Feed the output of fd into fzf
fd --type f --strip-cwd-prefix | fzf

# Setting fd as the default source for fzf
export FZF_DEFAULT_COMMAND='fd --type f --strip-cwd-prefix'

# Now fzf (w/o pipe) will use the fd command to generate the list
fzf

# To apply the command to CTRL-T as well
export FZF_CTRL_T_COMMAND="$FZF_DEFAULT_COMMAND"

If you want the command to follow symbolic links and don’t want it to exclude hidden files, use the following command:

`1`	`export FZF_DEFAULT_COMMAND='fd --type f --strip-cwd-prefix --hidden --follow --exclude .git'`

Fish shell

CTRL-T key binding of fish, unlike those of bash and zsh, will use the last token on the command-line as the root directory for the recursive search. For instance, hitting CTRL-T at the end of the following command-line

`1`	`ls /var/`

will list all files and directories under /var/.

When using a custom FZF_CTRL_T_COMMAND, use the unexpanded $dir variable to make use of this feature. $dir defaults to . when the last token is not a valid directory. Example:

`1`	`set -g FZF_CTRL_T_COMMAND "command find -L \$dir -type f 2> /dev/null \| sed '1d; s#^\./##'"`

fzf Theme Playground

fzf Theme Playground created by Vitor Mello is a webpage where you can interactively create fzf themes.

https://github.com/junegunn/fzf/wiki/Related-projects

License

The MIT License (MIT)

Sponsors :heart:

I would like to thank all the sponsors of this project who make it possible for me to continue to improve fzf.

If you’d like to sponsor this project, please visit https://github.com/sponsors/junegunn.

JetBrains supports this project with an Open Source Development License.

nexus-cli

Fri, 27 Jun 2025 15:30:32 +0800

nexus-xyz/nexus-cli

Nexus CLI

A high-performance command-line interface for contributing proofs to the Nexus network.

Verifiable Computation on a Global Scale
We're building a global distributed prover network to unite the world's computers and power a new and better Internet: the Verifiable Internet. Connect to the beta and give it a try today.

Nexus Network

Nexus is a global distributed prover network that unites the world’s computers to power a new and better Internet: the Verifiable Internet.

There have been several testnets so far:

Testnet 0: October 8 – 28, 2024
Testnet I: December 9 – 13, 2024
Testnet II: February 18 – 22, 2025
Devnet: February 22 - June 20 2025
Testnet III: Ongoing

Quick Start

Installation

Precompiled Binary (Recommended)

For the simplest and most reliable installation:

`1`	`curl https://cli.nexus.xyz/ \| sh`

This will:

Download and install the latest precompiled binary for your platform.
Prompt you to accept the Terms of Use.
Start the CLI in interactive mode.

The exact installation script is viewable here.

Non-Interactive Installation

For automated installations (e.g., in CI):

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curl -sSf https://cli.nexus.xyz/ -o install.sh
chmod +x install.sh
NONINTERACTIVE=1 ./install.sh

Proving

Proving with the CLI is documented here.

To start with an existing node ID, run:

`1`	`nexus-cli start --node-id <your-node-id>`

Alternatively, you can register your wallet address and create a node ID with the CLI, or at at app.nexus.xyz.

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nexus-cli register-user --wallet-address <your-wallet-address>
nexus-cli register-node
nexus-cli start

The register-user and register-node commands will save your credentials to ~/.nexus/config.json. To clear credentials, run:

`1`	`nexus-cli logout`

For troubleshooting or to see available command line options, run:

`1`	`nexus-cli --help`

Terms of Use

Use of the CLI is subject to the Terms of Use. First-time users running interactively will be prompted to accept these terms.

Node ID

During the CLI’s startup, you’ll be asked for your node ID. To skip prompts in a non-interactive environment, manually create a ~/.nexus/config.json in the following format:

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{
   "node_id": "<YOUR NODE ID>"
}

Current Limitations

To submit programs to the network for proving, contact growth@nexus.xyz.

Get Help

Contributing

Interested in contributing to the Nexus Network CLI? Check out our Contributor Guide for:

Development setup instructions
How to report issues and submit pull requests
Our code of conduct and community guidelines
Tips for working with the codebase

For most users, we recommend using the precompiled binaries as described above. The contributor guide is intended for those who want to modify or improve the CLI itself.

🛠 Developer Guide

The following steps may be required in order to setup a development environment for contributing to the project:

Linux

sudo apt update
sudo apt upgrade
sudo apt install build-essential pkg-config libssl-dev git-all
sudo apt install protobuf-compiler

macOS

# Install using Homebrew
brew install protobuf

# Verify installation
protoc --version

Windows

Install WSL, then see Linux instructions above.

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# Install using Chocolatey
choco install protobuf

Building ProtoBuf files

To build the ProtoBuf files, run the following command in the clients/cli directory:

`1`	`cargo build --features build_proto`

Creating a Release

To create a release, update the package version in Cargo.toml, then create and push a new (annotated) tag, e.g.:

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git tag -a v0.1.2 -m "Release v0.1.2"
git push origin v0.1.2

This will trigger the GitHub Actions release workflow that compiles binaries and pushes the Docker image, in addition to creating release.

WARNING: Creating a release through the GitHub UI creates a new release but does NOT trigger the workflow. This leads to a release without a Docker image or binaries, which breaks the installation script.

WSL

Fri, 23 May 2025 15:28:31 +0800

microsoft/WSL

Welcome to the Windows Subsystem for Linux (WSL) repository

Learn more about WSL | Downloads & Release notes | Contributing to WSL

About

Windows Subsystem for Linux (WSL) is a powerful way for you to run your Linux command-line tools, utilities and applications, all unmodified and directly on Windows without the overhead of a traditional virtual machine or dual boot setup.

You can install WSL right away by running this command inside of your Windows command line:

`1`	`wsl --install`

You can learn more about best practices for setup, overviews of WSL and more at our WSL documentation page.

WSL also has related open source repositories:

microsoft/WSL2-Linux-Kernel - The Linux kernel shipped with WSL
microsoft/WSLg - Support for Linux GUI apps in WSL
microsoftdocs/wsl - WSL documentation at aka.ms/wsldocs

Contributing

This project welcomes contributions of all types, including coding features / bug fixes, documentation fixes, design proposals and more.

We ask that before you start working on a contribution, please read our Contributor’s Guide.

For guidance on developing for WSL, please read the developer docs for instructions on how to build WSL from source and details on its architecture.

Code of Conduct

This project has adopted the Microsoft Open Source Code of Conduct

Trademarks

This project may contain trademarks or logos for projects, products, or services. Authorized use of Microsoft trademarks or logos is subject to and must follow Microsoft’s Trademark & Brand Guidelines. Use of Microsoft trademarks or logos in modified versions of this project must not cause confusion or imply Microsoft sponsorship. Any use of third-party trademarks or logos are subject to those third-party’s policies.

Privacy and telemetry

The application logs basic diagnostic data (telemetry). For more information on privacy and what we collect, see our data and privacy documentation.

The software may collect information about you and your use of the software and send it to Microsoft. Microsoft may use this information to provide services and improve our products and services. You may turn off the telemetry as described in the repository. There are also some features in the software that may enable you and Microsoft to collect data from users of your applications. If you use these features, you must comply with applicable law, including providing appropriate notices to users of your applications together with a copy of Microsoft’s privacy statement. Our privacy statement is located at https://go.microsoft.com/fwlink/?LinkID=824704. You can learn more about data collection and use in the help documentation and our privacy statement. Your use of the software operates as your consent to these practices.

douyin-downloader

Sat, 12 Apr 2025 15:24:42 +0800

jiji262/douyin-downloader

DouYin Downloader

DouYin Downloader 是一个用于批量下载抖音内容的工具。基于抖音 API 实现，支持命令行参数或 YAML 配置文件方式运行，可满足大部分抖音内容的下载需求。

✨ 特性

多种内容支持
- 视频、图集、音乐、直播信息下载
- 支持个人主页、作品分享、直播、合集、音乐集合等多种链接
- 支持去水印下载
批量下载能力
- 多线程并发下载
- 支持多链接批量下载
- 自动跳过已下载内容
灵活配置
- 支持命令行参数和配置文件两种方式
- 可自定义下载路径、线程数等
- 支持下载数量限制
增量更新
- 支持主页作品增量更新
- 支持数据持久化到数据库
- 可根据时间范围过滤

🚀 快速开始

安装

安装 Python 依赖：

`1`	`pip install -r requirements.txt`

复制配置文件：

`1`	`cp config.example.yml config.yml`

配置

编辑 config.yml 文件，设置：

下载链接
保存路径
Cookie 信息（从浏览器开发者工具获取）
其他下载选项

运行

方式一：使用配置文件（推荐）

`1`	`python DouYinCommand.py`

方式二：使用命令行

`1`	`python DouYinCommand.py -C True -l "抖音分享链接" -p "下载路径"`

使用交流群

使用截图

📝 支持的链接类型

作品分享链接：https://v.douyin.com/xxx/
个人主页：https://www.douyin.com/user/xxx
单个视频：https://www.douyin.com/video/xxx
图集：https://www.douyin.com/note/xxx
合集：https://www.douyin.com/collection/xxx
音乐原声：https://www.douyin.com/music/xxx
直播：https://live.douyin.com/xxx

🛠️ 高级用法

命令行参数

基础参数：

-C, --cmd            使用命令行模式
-l, --link          下载链接
-p, --path          保存路径
-t, --thread        线程数（默认5）

下载选项：

-m, --music         下载音乐（默认True）
-c, --cover         下载封面（默认True）
-a, --avatar        下载头像（默认True）
-j, --json          保存JSON数据（默认True）

更多参数说明请使用 -h 查看帮助信息。

示例命令

下载单个视频：

`1`	`python DouYinCommand.py -C True -l "https://v.douyin.com/xxx/"`

下载主页作品：

`1`	`python DouYinCommand.py -C True -l "https://v.douyin.com/xxx/" -M post`

批量下载：

`1`	`python DouYinCommand.py -C True -l "链接1" -l "链接2" -p "./downloads"`

更多示例请参考使用示例文档。

📋 注意事项

本项目仅供学习交流使用
使用前请确保已安装所需依赖
Cookie 信息需要自行获取
建议适当调整线程数，避免请求过于频繁

🤝 贡献

欢迎提交 Issue 和 Pull Request。

📜 许可证

本项目采用 MIT 许可证。

🙏 鸣谢

TikTokDownload
本项目使用了 ChatGPT 辅助开发，如有问题请提 Issue

📊 Star History

License

MIT

Command Line on Producthunt daily

tesseract

Tesseract OCR

Table of Contents

About

Brief history

Installing Tesseract

Running Tesseract

For developers

Support

License

Dependencies

Latest Version of README

coreutils

uutils coreutils

Goals

Documentation

Requirements

Rust Version

Building

Cargo

GNU Make

Installation

Install with Cargo

Install with GNU Make

Manually install shell completions

Manually install manpages

Un-installation

Uninstall with Cargo

Uninstall with GNU Make

GNU test suite compatibility

Contributing

License

spotify-downloader

spotDL v4

Installation

Python (Recommended Method)

Installing FFmpeg

Usage

Music Sourcing and Audio Quality

Audio Quality

Contributing

Join our amazing community as a code contributor

License

the-art-of-command-line

The Art of Command Line

Meta

Basics

Everyday use

Processing files and data

System debugging

One-liners

Obscure but useful

macOS only

Windows only

Ways to obtain Unix tools under Windows

Useful Windows command-line tools

Cygwin tips and tricks

More resources

Disclaimer

License

tldr

What is tldr-pages?

How do I use it?

How do I contribute to tldr-pages?

Similar projects

What does “tldr” mean?

OCRmyPDF

Main features

Motivation

Installation

Languages

Documentation and support

Feature demo

Requirements

Press & Media

Business enquiries

License

Disclaimer

fzf

`--height` mode

`--tmux` mode

Respecting `.gitignore`