Session and utilities

The readonly command

Marks a variable as read-only: it cannot be changed or deleted during the session.

Syntax

readonly NOMBRE=valor

Most useful options

-pLists the read-only variables

Copy-ready examples

$ readonly FIJO=7 && readonlyDefine and list

You can try them in the browser terminal: it does not touch your computer.

Typical mistakes

  • It cannot be undone in the same session: you must open a new terminal.

Related commands

setunsetexport

FAQ

What is it for?

To protect configuration constants in long scripts.

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