local:tldr:3d374

This command sets a local variable with a read-only attribute in a shell script. Here's how it works:

• local is a shell built-in command that is used to declare local variables within a function or a block of code. It ensures that the variable is only accessible within that particular scope.
• -r is an option for the local command, which declares the variable as read-only. Once a variable is set as read-only, its value cannot be modified or reassigned.
• ${variable} is a placeholder that should be replaced with the name you want to give to the variable. It can be any valid variable name.
• "${value}" is a placeholder that should be replaced with the value you want to assign to the variable. It can be any valid value, such as a string, number, or another variable.

Putting it all together, the command local -r ${variable}="${value}" declares a local variable named ${variable} and sets its value to ${value}. This variable is then made read-only, so its value cannot be changed later in the script.