Internal variables

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Introduction

An overview of Bash’s internal variables, where, how, and when to use them.

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Internal variables:

*Internal variables

*Bash internal variables at a glance

*

*

*HOME

*etc...

*

*FUNCNAME

*

*

*PWD

*HISTSIZE

*IFS

*

*OLDPWD

*PATH

*OSTYPE

*MACHTYPE

*PPID

*HOSTTYPE

*SECONDS

*SHELLOPTS

*HOSTNAME

*EDITOR

*BASH VERSION

*BASH VERSINFO

*BASH ENV

*BASHPID

*

*RANDOM

*SHLVL

*LINENO

*GROUPS

*UID

Table Of Contents

0Getting started

1Using trap to react to signals and system events

2Listing files

3Aliasing

4Jobs and processes

5Redirection

6Control structures

7Using cat

8Arrays

9Functions

10Bash Parameter Expansion

11Sourcing

12Find

13Here documents and here strings

14Quoting

15Conditional Expressions

16Scripting with parameters

17History substitutions

18Math

19Scoping

20Process substitution

21Programmable completion

22Customizing PS1

23Brace Expansion

24Bash Arithmetic

25getopts smart positional-parameter parsing

26Debugging

27Pitfalls

28Script shebang

29Pattern matching and regular expressions

30Keyboard shortcuts

31Change shell

32Copying with cp

33Internal variables

34Job control

35Case statement

36Word splitting

37Read a file

38File transfer with scp

39Pipelines

40Managing PATH environment variable

41Avoiding date using printf

42Chain of commands and operations

43Type of shells

44true, false and commands

45Color script output cross-platform

46Navigating directories

47Using sort

48Namespace

49co-processes

50Typing variables

51Jobs at specific types

52Associative arrays

53Handling the system prompt

54Creating directories

55File execution sequence

56The cut command

57Bash on Windows 10

58Cut command

59Splitting files

60Global and local variables

61Design Patterns

62CGI Scripts

63Select keyword

64When to use eval

65Networking with bash

66Parallel

67Grep

68Strace

69Sleep

70Decodi

71Contributors