README

NEW: pure sh bible (📖 A collection of pure POSIX sh alternatives to external processes).




pure bash bible A collection of pure bash alternatives to external
processes.

 









The goal of this book is to document commonly-known and lesser-known methods of doing various tasks using only built-in bash features. Using the snippets from this bible can help remove unneeded dependencies from scripts and in most cases make them faster. I came across these tips and discovered a few while developing neofetch, pxltrm and other smaller projects.

The snippets below are linted using shellcheck and tests have been written where applicable. Want to contribute? Read the CONTRIBUTING.md. It outlines how the unit tests work and what is required when adding snippets to the bible.

See something incorrectly described, buggy or outright wrong? Open an issue or send a pull request. If the bible is missing something, open an issue and a solution will be found.


This book is also available to purchase on leanpub. https://leanpub.com/bash
Or you can buy me a coffee.
  




 Table of Contents



 FOREWORD
 STRINGS
     Trim leading and trailing white-space from string
     Trim all white-space from string and truncate spaces
     Use regex on a string
     Split a string on a delimiter
     Change a string to lowercase
     Change a string to uppercase
     Reverse a string case
     Trim quotes from a string
     Strip all instances of pattern from string
     Strip first occurrence of pattern from string
     Strip pattern from start of string
     Strip pattern from end of string
     Percent-encode a string
     Decode a percent-encoded string
     Check if string contains a sub-string
     Check if string starts with sub-string
     Check if string ends with sub-string
 ARRAYS
     Reverse an array
     Remove duplicate array elements
     Random array element
     Cycle through an array
     Toggle between two values
 LOOPS
     Loop over a range of numbers
     Loop over a variable range of numbers
     Loop over an array
     Loop over an array with an index
     Loop over the contents of a file
     Loop over files and directories
 FILE HANDLING
     Read a file to a string
     Read a file to an array (by line)
     Get the first N lines of a file
     Get the last N lines of a file
     Get the number of lines in a file
     Count files or directories in directory
     Create an empty file
     Extract lines between two markers
 FILE PATHS
     Get the directory name of a file path
     Get the base-name of a file path
 VARIABLES
     Assign and access a variable using a variable
     Name a variable based on another variable
 ESCAPE SEQUENCES
     Text Colors
     Text Attributes
     Cursor Movement
     Erasing Text
 PARAMETER EXPANSION
     Indirection
     Replacement
     Length
     Expansion
     Case Modification
     Default Value
 BRACE EXPANSION
     Ranges
     String Lists
 CONDITIONAL EXPRESSIONS
     File Conditionals
     File Comparis

Top issues