How to capitalize Bash and shell script variable?

Bash and shell script variable capitalization?

In Bash and other shell scripts, variable names are case-sensitive. This means that myVariable and MYVARIABLE are two distinct variables.

By convention, variable names in Bash are written in lowercase or with underscores (_) to separate words. The use of uppercase letters is generally avoided, except in a few cases. Here are some guidelines for capitalization in Bash variable names:

  • Use lowercase letters for most variable names.
  • Use underscores (_) to separate multiple words in a variable name.
  • Use uppercase letters for global variables, which are variables that are used throughout a script or multiple scripts.
  • Use uppercase letters for Bash built-in variables, such as $HOME, $PATH, and $IFS.

Here are some examples:

#!/bin/bash

# lowercase variable
myvar="hello"

# lowercase variable with underscores
my_var="world"

# global variable (uppercase)
MY_GLOBAL_VAR="hello world"

# Bash built-in variable (uppercase)
echo "My home directory is $HOME"

It's generally a good idea to follow these naming conventions to make your code more readable and easier to understand, both for yourself and others who may read it later.

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