function::user_string - Linux


function::user_string() is a command used to manage and manipulate user-defined strings in Linux. It provides a convenient way to store, retrieve, and modify string values associated with specific keys. This command is particularly useful for storing configuration data, environment variables, and other data that needs to be accessed or modified at runtime.


function::user_string [-h] [-g KEY] [-s KEY] [-d KEY] [-l] [-a KEY VALUE]


  • -h, –help: Displays help information about the command.
  • -g, –get: Retrieves the value associated with the specified KEY.
  • -s, –set: Sets the value associated with the specified KEY.
  • -d, –delete: Deletes the key-value pair associated with the specified KEY.
  • -l, –list: Lists all the keys and their associated values.
  • -a, –add: Adds a new key-value pair or updates the value of an existing key.


Retrieve a value:

function::user_string -g my_key

Set a value:

function::user_string -s my_key "Hello World!"

Delete a value:

function::user_string -d my_key

Add or update a value:

function::user_string -a my_key "Updated Value"

List all keys and values:

function::user_string -l

Common Issues

  • If the specified key does not exist, the -g option will return an empty string.
  • If the -s or -a options are used without specifying a value, the value will be set to an empty string.
  • If the -d option is used without specifying a key, all key-value pairs will be deleted.


function::user_string can be integrated with other Linux commands to perform advanced tasks. For example, you can use it to store and retrieve environment variables:

export MY_VAR=$(function::user_string -g my_var)

Related Commands

  • env: Manipulates environment variables.
  • sed: Performs text substitution and manipulation.