993 lines
20 KiB
Markdown
993 lines
20 KiB
Markdown
<h1 align="center">pure bash bible</h1> <p
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align="center">A [WIP] collection of pure bash alternatives to external
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processes.</p>
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<p align="center">
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<a href="https://travis-ci.com/dylanaraps/pure-bash"><img
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src="https://travis-ci.com/dylanaraps/pure-bash.svg?branch=master"></a> <a
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href="./LICENSE.md"><img
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src="https://img.shields.io/badge/license-MIT-blue.svg"></a>
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</p>
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<br>
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The goal of this repository is to document known and unknown methods of
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doing various tasks using only built-in bash features. Using the snippets
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from this guide can help to remove unneeded dependencies from your scripts
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and in most cases make them that little bit faster. I came across these
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tips and discovered a few while developing
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[neofetch](https://github.com/dylanaraps/neofetch),
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[pxltrm](https://github.com/dylanaraps/pxltrm) and some other smaller
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projects.
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This repository is open to contribution. If you see something that is
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incorrectly described, buggy or outright wrong, open an issue or send a
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pull request. If you know a handy snippet that is not included in this
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list, send a pull request!
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**NOTE**: Error handling (*checking if a file exists, etc*) is not
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included. These are meant to be snippets you can incorporate into your
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scripts and not full blown utilities.
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<br>
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## Table of Contents
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<!-- vim-markdown-toc GFM -->
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* [Strings](#strings)
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* [Trim leading and trailing white-space from string.](#trim-leading-and-trailing-white-space-from-string)
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* [Trim all white-space from string and truncate spaces.](#trim-all-white-space-from-string-and-truncate-spaces)
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* [Use REGEX on a string.](#use-regex-on-a-string)
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* [Split a string on a delimiter.](#split-a-string-on-a-delimiter)
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* [Change a string to lowercase.](#change-a-string-to-lowercase)
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* [Change a string to uppercase.](#change-a-string-to-uppercase)
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* [Trim quotes from a string.](#trim-quotes-from-a-string)
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* [Strip all instances of pattern from string.](#strip-all-instances-of-pattern-from-string)
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* [Strip first occurrence of pattern from string.](#strip-first-occurrence-of-pattern-from-string)
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* [Strip pattern from start of string.](#strip-pattern-from-start-of-string)
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* [Strip pattern from end of string.](#strip-pattern-from-end-of-string)
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* [Variables](#variables)
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* [Assign and access a variable using a variable.](#assign-and-access-a-variable-using-a-variable)
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* [Arrays](#arrays)
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* [Reverse an array.](#reverse-an-array)
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* [Remove duplicate array elements.](#remove-duplicate-array-elements)
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* [Cycle through an array.](#cycle-through-an-array)
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* [Toggle between two values.](#toggle-between-two-values)
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* [File handling](#file-handling)
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* [Read a file to a string.](#read-a-file-to-a-string)
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* [Read a file to an array (*by line*).](#read-a-file-to-an-array-by-line)
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* [Get the first N lines of a file.](#get-the-first-n-lines-of-a-file)
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* [Get the last N lines of a file.](#get-the-last-n-lines-of-a-file)
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* [Get the number of lines in a file.](#get-the-number-of-lines-in-a-file)
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* [Iterate over files.](#iterate-over-files)
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* [Count files or directories in directory.](#count-files-or-directories-in-directory)
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* [Create an empty file.](#create-an-empty-file)
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* [File Paths](#file-paths)
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* [Get the directory name of a file path.](#get-the-directory-name-of-a-file-path)
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* [Get the base-name of a file path.](#get-the-base-name-of-a-file-path)
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* [Arithmetic](#arithmetic)
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* [Simpler syntax to set variables.](#simpler-syntax-to-set-variables)
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* [Ternary tests.](#ternary-tests)
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* [Colors](#colors)
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* [Convert a hex color to RGB.](#convert-a-hex-color-to-rgb)
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* [Convert an RGB color to hex.](#convert-an-rgb-color-to-hex)
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* [Information about the terminal](#information-about-the-terminal)
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* [Get the terminal size in lines and columns (*from a script*).](#get-the-terminal-size-in-lines-and-columns-from-a-script)
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* [Get the terminal size in pixels.](#get-the-terminal-size-in-pixels)
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* [Get the current cursor position.](#get-the-current-cursor-position)
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* [Code Golf](#code-golf)
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* [Shorter `for` loop syntax.](#shorter-for-loop-syntax)
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* [Shorter infinite loops.](#shorter-infinite-loops)
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* [Shorter function declaration.](#shorter-function-declaration)
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* [Shorter `if` syntax.](#shorter-if-syntax)
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* [Simpler `case` statement to set variable.](#simpler-case-statement-to-set-variable)
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* [Internal Variables](#internal-variables)
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* [Get the location to the `bash` binary.](#get-the-location-to-the-bash-binary)
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* [Get the version of the current running `bash` process.](#get-the-version-of-the-current-running-bash-process)
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* [Open the user's preferred text editor.](#open-the-users-preferred-text-editor)
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* [Get the name of the current function.](#get-the-name-of-the-current-function)
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* [Get the host-name of the system.](#get-the-host-name-of-the-system)
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* [Get the architecture of the Operating System.](#get-the-architecture-of-the-operating-system)
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* [Get the name of the Operating System / Kernel.](#get-the-name-of-the-operating-system--kernel)
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* [Get the current working directory.](#get-the-current-working-directory)
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* [Get the number of seconds the script has been running.](#get-the-number-of-seconds-the-script-has-been-running)
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* [Other](#other)
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* [Get the current date using `strftime`.](#get-the-current-date-using-strftime)
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* [Bypass shell aliases.](#bypass-shell-aliases)
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* [Bypass shell functions.](#bypass-shell-functions)
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<!-- vim-markdown-toc -->
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## Strings
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### Trim leading and trailing white-space from string.
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**Example Function:**
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```sh
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trim_string() {
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# Usage: trim_string " example string "
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: "${1#"${1%%[![:space:]]*}"}"
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: "${_%"${_##*[![:space:]]}"}"
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printf '%s\n' "$_"
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}
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```
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**Example Usage:**
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```shell
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$ trim_string " Hello, World "
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Hello, World
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$ name=" John Black "
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$ trim_string "$name"
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John Black
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```
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### Trim all white-space from string and truncate spaces.
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**Example Function:**
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```sh
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# shellcheck disable=SC2086,SC2048
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trim_all() {
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# Usage: trim_all " example string "
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set -f
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set -- $*
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printf '%s\n' "$*"
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set +f
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}
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```
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**Example Usage:**
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```shell
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$ trim_all " Hello, World "
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Hello, World
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$ name=" John Black is my name. "
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$ trim_all "$name"
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John Black is my name.
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```
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### Use REGEX on a string.
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We can use the result of `bash`'s regex matching to create a simple `sed`
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replacement.
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**NOTE**: This is one of the few platform dependant `bash` features.
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`bash` will use whatever regex engine is installed on the user's system.
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Stick to POSIX regex features if aiming for compatibility.
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**NOTE**: This example only prints the first matching group. When using
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multiple capture groups some modification will be needed.
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**Example Function:**
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```sh
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regex() {
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# Usage: regex "string" "regex"
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[[ $1 =~ $2 ]] && printf '%s\n' "${BASH_REMATCH[1]}"
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}
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```
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**Example Usage:**
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```shell
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$ # Trim leading white-space.
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$ regex ' hello' '^\s*(.*)'
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hello
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$ # Validate a hex color.
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$ regex "#FFFFFF" '^(#?([a-fA-F0-9]{6}|[a-fA-F0-9]{3}))$'
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#FFFFFF
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$ # Validate a hex color (invalid).
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$ regex "red" '^(#?([a-fA-F0-9]{6}|[a-fA-F0-9]{3}))$'
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# no output (invalid)
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```
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**Example Usage in script:**
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```shell
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is_hex_color() {
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if [[ "$1" =~ ^(#?([a-fA-F0-9]{6}|[a-fA-F0-9]{3}))$ ]]; then
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printf '%s\n' "${BASH_REMATCH[1]}"
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else
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printf '%s\n' "error: $1 is an invalid color."
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return 1
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fi
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}
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read -r color
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is_hex_color "$color" || color="#FFFFFF"
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# Do stuff.
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```
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### Split a string on a delimiter.
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```shell
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string="1,2,3"
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# To multiple variables.
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IFS=, read -r var1 var2 var3 <<< "$string"
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# To an array.
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IFS=, read -ra vars <<< "$string"
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```
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### Change a string to lowercase.
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**NOTE:** Requires `bash` 4+
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**Example Function:**
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```sh
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lower() {
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# Usage: lower "string"
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printf '%s\n' "${1,,}"
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}
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```
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**Example Usage:**
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```shell
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$ lower "HELLO"
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hello
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$ lower "HeLlO"
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hello
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$ lower "hello"
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hello
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```
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### Change a string to uppercase.
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**NOTE:** Requires `bash` 4+
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**Example Function:**
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```sh
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upper() {
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# Usage: upper "string"
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printf '%s\n' "${1^^}"
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}
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```
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**Example Usage:**
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```shell
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$ upper "hello"
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HELLO
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$ upper "HeLlO"
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HELLO
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$ upper "HELLO"
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HELLO
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```
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### Trim quotes from a string.
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**Example Function:**
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```sh
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trim_quotes() {
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# Usage: trim_quotes "string"
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: "${1//\'}"
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printf "%s\\n" "${_//\"}"
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}
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```
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**Example Usage:**
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```shell
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$ var="'Hello', \"World\""
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$ trim_quotes "$var"
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Hello, World
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```
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### Strip all instances of pattern from string.
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**Example Function:**
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```sh
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strip_all() {
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# Usage: strip_all "string" "pattern"
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printf '%s\n' "${1//$2}"
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}
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```
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**Example Usage:**
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```shell
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$ strip_all "The Quick Brown Fox" "[aeiou]"
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Th Qck Brwn Fx
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$ strip_all "The Quick Brown Fox" "[[:space:]]"
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TheQuickBrownFox
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$ strip_all "The Quick Brown Fox" "Quick "
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The Brown Fox
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```
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### Strip first occurrence of pattern from string.
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**Example Function:**
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```sh
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strip() {
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# Usage: strip "string" "pattern"
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printf '%s\n' "${1/$2}"
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}
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```
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**Example Usage:**
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```shell
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$ strip "The Quick Brown Fox" "[aeiou]"
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Th Quick Brown Fox
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$ strip "The Quick Brown Fox" "[[:space:]]"
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TheQuick Brown Fox
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```
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### Strip pattern from start of string.
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**Example Function:**
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```sh
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lstrip() {
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# Usage: lstrip "string" "pattern"
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printf '%s\n' "${1##$2}"
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}
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```
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**Example Usage:**
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```shell
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$ lstrip "The Quick Brown Fox" "The "
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Quick Brown Fox
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```
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### Strip pattern from end of string.
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**Example Function:**
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```sh
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rstrip() {
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# Usage: rstrip "string" "pattern"
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printf '%s\n' "${1%%$2}"
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}
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```
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**Example Usage:**
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```shell
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$ rstrip "The Quick Brown Fox" " Fox"
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The Quick Brown
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```
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## Variables
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### Assign and access a variable using a variable.
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```shell
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hello_world="test"
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# Create the variable name.
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var1="world"
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var2="hello_${var1}"
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# Print the value of the variable name stored in 'hello_$var1'.
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printf '%s\n' "${!var2}"
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```
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## Arrays
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### Reverse an array.
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Enabling `extdebug` allows access to the `BASH_ARGV` array which stores
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the current function’s arguments in reverse.
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**Example Function:**
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```sh
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reverse_array() {
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# Usage: reverse_array "array"
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shopt -s extdebug
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f()(printf '%s\n' "${BASH_ARGV[@]}"); f "$@"
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shopt -u extdebug
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}
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```
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**Example Usage:**
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```shell
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$ reverse_array 1 2 3 4 5
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5
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4
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3
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2
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1
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$ arr=(red blue green)
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$ reverse_array "${arr[@]}"
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green
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blue
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red
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```
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### Remove duplicate array elements.
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Create a temporary associative array. When setting associative array
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values and a duplicate assignment occurs, bash overwrites the key. This
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allows us to effectively remove array duplicates.
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**NOTE:** Requires `bash` 4+
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**Example Function:**
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```sh
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remove_array_dups() {
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# Usage: remove_array_dups "array"
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declare -A tmp_array
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for i in "$@"; do
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[[ "$i" ]] && IFS=" " tmp_array["${i:- }"]=1
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done
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printf '%s\n' "${!tmp_array[@]}"
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}
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```
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```shell
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$ remove_array_dups 1 1 2 2 3 3 3 3 3 4 4 4 4 4 5 5 5 5 5 5
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1
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2
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3
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4
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5
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$ arr=(red red green blue blue)
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$ remove_array_dups "${arr[@]}"
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red
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green
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blue
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```
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### Cycle through an array.
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Each time the `printf` is called, the next array element is printed. When
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the print hits the last array element it starts from the first element
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again.
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```sh
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arr=(a b c d)
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cycle() {
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printf '%s ' "${arr[${i:=0}]}"
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((i=i>=${#arr[@]}-1?0:++i))
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}
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```
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### Toggle between two values.
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This works the same as above, this is just a different use case.
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```sh
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arr=(true false)
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cycle() {
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printf '%s ' "${arr[${i:=0}]}"
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((i=i>=${#arr[@]}-1?0:++i))
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}
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```
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## File handling
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### Read a file to a string.
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Alternative to the `cat` command.
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```shell
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file_data="$(<"file")"
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```
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### Read a file to an array (*by line*).
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Alternative to the `cat` command.
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```shell
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# Bash <4
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IFS=$'\n' read -d "" -ra file_data < "file"
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# Bash 4+
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mapfile -t file_data < "file"
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```
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### Get the first N lines of a file.
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Alternative to the `head` command.
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**NOTE:** Requires `bash` 4+
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```sh
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head() {
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# Usage: head "n" "file"
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mapfile -tn "$1" line < "$2"
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printf '%s\n' "${line[@]}"
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}
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```
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### Get the last N lines of a file.
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Alternative to the `tail` command.
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**NOTE:** Requires `bash` 4+
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```sh
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tail() {
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# Usage: tail "n" "file"
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mapfile -tn 0 line < "$2"
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printf '%s\n' "${line[@]: -$1}"
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}
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```
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### Get the number of lines in a file.
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Alternative to `wc -l`.
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**NOTE:** Requires `bash` 4+
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```sh
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lines() {
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# Usage lines "file"
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mapfile -tn 0 lines < "$1"
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printf '%s\n' "${#lines[@]}"
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}
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```
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### Iterate over files.
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Don’t use `ls`.
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```sh
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_() {
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# Greedy example.
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for file in *; do
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printf '%s\n' "$file"
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done
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# PNG files in dir.
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for file in ~/Pictures/*.png; do
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printf '%s\n' "$file"
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done
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# Iterate over directories.
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for dir in ~/Downloads/*/; do
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printf '%s\n' "$dir"
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done
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# Iterate recursively.
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shopt -s globstar
|
||
for file in ~/Pictures/**/*; do
|
||
printf '%s\n' "$file"
|
||
done
|
||
shopt -u globstar
|
||
}
|
||
```
|
||
|
||
### Count files or directories in directory.
|
||
|
||
This works by passing the output of the glob as function arguments. We
|
||
then count the arguments and print the number.
|
||
|
||
```sh
|
||
count() {
|
||
# Usage: count /path/to/dir/*
|
||
# count /path/to/dir/*/
|
||
printf '%s\n' "$#"
|
||
}
|
||
```
|
||
|
||
### Create an empty file.
|
||
|
||
Alternative to `touch`.
|
||
|
||
```sh
|
||
_() {
|
||
# Shortest.
|
||
:> file
|
||
|
||
# Longer alternatives:
|
||
echo -n > file
|
||
printf '' > file
|
||
}
|
||
```
|
||
|
||
## File Paths
|
||
|
||
### Get the directory name of a file path.
|
||
|
||
Alternative to the `dirname` command.
|
||
|
||
```sh
|
||
dirname() {
|
||
# Usage: dirname "path"
|
||
printf '%s\n' "${1%/*}/"
|
||
}
|
||
```
|
||
|
||
### Get the base-name of a file path.
|
||
|
||
Alternative to the `basename` command.
|
||
|
||
```sh
|
||
basename() {
|
||
# Usage: basename "path"
|
||
: "${1%/}"
|
||
printf '%s\n' "${_##*/}"
|
||
}
|
||
```
|
||
|
||
## Arithmetic
|
||
|
||
### Simpler syntax to set variables.
|
||
|
||
```sh
|
||
_() {
|
||
# Simple math
|
||
((var=1+2))
|
||
|
||
# Decrement/Increment variable
|
||
((var++))
|
||
((var--))
|
||
((var+=1))
|
||
((var-=1))
|
||
|
||
# Using variables
|
||
((var=var2*arr[2]))
|
||
}
|
||
```
|
||
|
||
### Ternary tests.
|
||
|
||
```sh
|
||
_() {
|
||
# Set the value of var to var2 if var2 is greater than var.
|
||
# var: variable to set.
|
||
# var2>var: Condition to test.
|
||
# ?var2: If the test succeeds.
|
||
# :var: If the test fails.
|
||
((var=var2>var?var2:var))
|
||
}
|
||
```
|
||
|
||
## Colors
|
||
|
||
### Convert a hex color to RGB.
|
||
|
||
```sh
|
||
hex_to_rgb() {
|
||
# Usage: hex_to_rgb "#FFFFFF"
|
||
((r=16#${1:1:2}))
|
||
((g=16#${1:3:2}))
|
||
((b=16#${1:5:6}))
|
||
|
||
printf '%s\n' "$r $g $b"
|
||
}
|
||
```
|
||
|
||
### Convert an RGB color to hex.
|
||
|
||
```sh
|
||
rgb_to_hex() {
|
||
# Usage: rgb_to_hex "r" "g" "b"
|
||
printf '#%02x%02x%02x\n' "$1" "$2" "$3"
|
||
}
|
||
```
|
||
|
||
## Information about the terminal
|
||
|
||
### Get the terminal size in lines and columns (*from a script*).
|
||
|
||
This is handy when writing scripts in pure bash and `stty`/`tput` can’t be
|
||
called.
|
||
|
||
```sh
|
||
get_term_size() {
|
||
# Usage: get_term_size
|
||
|
||
# (:;:) is a micro sleep to ensure the variables are
|
||
# exported immediately.
|
||
shopt -s checkwinsize; (:;:)
|
||
printf '%s\n' "$LINES $COLUMNS"
|
||
}
|
||
```
|
||
|
||
### Get the terminal size in pixels.
|
||
|
||
**NOTE**: This does not work in some terminal emulators.
|
||
|
||
```sh
|
||
get_window_size() {
|
||
# Usage: get_window_size
|
||
printf '%b' "${TMUX:+\\ePtmux;\\e}\\e[14t${TMUX:+\\e\\\\}"
|
||
IFS=';t' read -d t -t 0.05 -sra term_size
|
||
printf '%s\n' "${term_size[1]}x${term_size[2]}"
|
||
}
|
||
```
|
||
|
||
### Get the current cursor position.
|
||
|
||
This is useful when creating a TUI in pure bash.
|
||
|
||
```sh
|
||
get_cursor_pos() {
|
||
# Usage: get_cursor_pos
|
||
IFS='[;' read -p $'\e[6n' -d R -rs _ y x _
|
||
printf '%s\n' "$x $y"
|
||
}
|
||
```
|
||
|
||
## Code Golf
|
||
|
||
### Shorter `for` loop syntax.
|
||
|
||
```sh
|
||
_() {
|
||
# Tiny C Style.
|
||
for((;i++<10;)){ echo "$i";}
|
||
|
||
# Undocumented method.
|
||
# Note: This is commented to make shellcheck play nice.
|
||
# for i in {1..10};{ echo "$i";}
|
||
|
||
# Expansion.
|
||
for i in {1..10}; do echo "$i"; done
|
||
|
||
# C Style.
|
||
for((i=0;i<=10;i++)); do echo "$i"; done
|
||
}
|
||
```
|
||
|
||
### Shorter infinite loops.
|
||
|
||
```sh
|
||
_() {
|
||
# Normal method
|
||
while :; do echo hi; done
|
||
|
||
# Shorter
|
||
for((;;)){ echo hi;}
|
||
}
|
||
```
|
||
|
||
### Shorter function declaration.
|
||
|
||
```sh
|
||
_() {
|
||
# Normal method
|
||
f(){ echo hi;}
|
||
|
||
# Using a subshell
|
||
f()(echo hi)
|
||
|
||
# Using arithmetic
|
||
# You can use this to assign integer values.
|
||
# Example: f a=1
|
||
# f a++
|
||
f()(($1))
|
||
|
||
# Using tests, loops etc.
|
||
# NOTE: You can also use ‘while’, ‘until’, ‘case’, ‘(())’, ‘[[]]’.
|
||
# NOTE: These are commented to make shellcheck play nice.
|
||
# f()if true; then echo "$1"; fi
|
||
# f()for i in "$@"; do echo "$i"; done
|
||
}
|
||
```
|
||
|
||
### Shorter `if` syntax.
|
||
|
||
```sh
|
||
_() {
|
||
# One line
|
||
[[ "$var" == hello ]] && echo hi || echo bye
|
||
[[ "$var" == hello ]] && { echo hi; echo there; } || echo bye
|
||
|
||
# Multi line (no else, single statement)
|
||
[[ "$var" == hello ]] && \
|
||
echo hi
|
||
|
||
# Multi line (no else)
|
||
[[ "$var" == hello ]] && {
|
||
echo hi
|
||
# ...
|
||
}
|
||
}
|
||
```
|
||
|
||
### Simpler `case` statement to set variable.
|
||
|
||
We can use the `:` builtin to avoid repeating `variable=` in a case
|
||
statement. The `$_` variable stores the last argument of the last
|
||
successful command. `:` always succeeds so we can abuse it to store the
|
||
variable value.
|
||
|
||
```sh
|
||
_() {
|
||
# Example snippet from Neofetch.
|
||
case "$(uname)" in
|
||
"Linux" | "GNU"*)
|
||
: "Linux"
|
||
;;
|
||
|
||
*"BSD" | "DragonFly" | "Bitrig")
|
||
: "BSD"
|
||
;;
|
||
|
||
"CYGWIN"* | "MSYS"* | "MINGW"*)
|
||
: "Windows"
|
||
;;
|
||
|
||
*)
|
||
printf '%s\n' "Unknown OS detected, aborting..." >&2
|
||
exit 1
|
||
;;
|
||
esac
|
||
|
||
# Finally, set the variable.
|
||
os="$_"
|
||
}
|
||
```
|
||
|
||
## Internal Variables
|
||
|
||
**NOTE**: This list does not include every internal variable (*You can
|
||
help by adding a missing entry!*).
|
||
|
||
For a complete list, see:
|
||
http://tldp.org/LDP/abs/html/internalvariables.html
|
||
|
||
### Get the location to the `bash` binary.
|
||
|
||
```sh
|
||
: "$BASH"
|
||
```
|
||
|
||
### Get the version of the current running `bash` process.
|
||
|
||
```sh
|
||
# As a string.
|
||
: "$BASH_VERSION"
|
||
|
||
# As an array.
|
||
: "${BASH_VERSINFO[@]}"
|
||
```
|
||
|
||
### Open the user's preferred text editor.
|
||
|
||
```sh
|
||
: "$EDITOR" "$file"
|
||
|
||
# NOTE: This variable may be empty, set a fallback value.
|
||
: "${EDITOR:-vi}" "$file"
|
||
```
|
||
|
||
### Get the name of the current function.
|
||
|
||
```sh
|
||
# Current function.
|
||
: "${FUNCNAME[0]}"
|
||
|
||
# Parent function.
|
||
: "${FUNCNAME[1]}"
|
||
|
||
# So on and so forth.
|
||
: "${FUNCNAME[2]}"
|
||
: "${FUNCNAME[3]}"
|
||
|
||
# All functions including parents.
|
||
: "${FUNCNAME[@]}"
|
||
```
|
||
|
||
### Get the host-name of the system.
|
||
|
||
```sh
|
||
: "$HOSTNAME"
|
||
|
||
# NOTE: This variable may be empty.
|
||
# Optionally set a fallback to the hostname command.
|
||
: "${HOSTNAME:-$(hostname)}"
|
||
```
|
||
|
||
### Get the architecture of the Operating System.
|
||
|
||
```sh
|
||
: "$HOSTTYPE"
|
||
```
|
||
|
||
### Get the name of the Operating System / Kernel.
|
||
|
||
This can be used to add conditional support for different Operating
|
||
Systems without needing to call `uname`.
|
||
|
||
```sh
|
||
: "$OSTYPE"
|
||
```
|
||
|
||
### Get the current working directory.
|
||
|
||
This is an alternative to the `pwd` built-in.
|
||
|
||
```sh
|
||
: "$PWD"
|
||
```
|
||
|
||
### Get the number of seconds the script has been running.
|
||
|
||
```sh
|
||
: "$SECONDS"
|
||
```
|
||
|
||
## Other
|
||
|
||
### Get the current date using `strftime`.
|
||
|
||
Bash’s `printf` has a built-in method of getting the date which we can use
|
||
in place of the `date` command in a lot of cases.
|
||
|
||
**NOTE:** Requires `bash` 4+
|
||
|
||
```sh
|
||
date() {
|
||
# Usage: date "format"
|
||
# See: 'man strftime' for format.
|
||
printf "%($1)T\\n" "-1"
|
||
}
|
||
|
||
# Examples:
|
||
|
||
# Using date.
|
||
: date "+%a %d %b - %l:%M %p"
|
||
|
||
# Using printf.
|
||
: printf '%(%a %d %b - %l:%M %p)T\n' '-1'
|
||
|
||
# Assigning a variable.
|
||
: printf -v date '%(%a %d %b - %l:%M %p)T\n' '-1'
|
||
```
|
||
|
||
### Bypass shell aliases.
|
||
|
||
```sh
|
||
# alias
|
||
: ls
|
||
|
||
# command
|
||
# shellcheck disable=SC1001
|
||
: \ls
|
||
```
|
||
|
||
### Bypass shell functions.
|
||
|
||
```sh
|
||
# function
|
||
: ls
|
||
|
||
# command
|
||
: command ls
|
||
```
|
||
|