export Command in Linux

Syntax of export Command in Linux

The basic syntax of the export command in Linux is as follows:

Where:

• -nf: These are options that can be used with the export command. '-n' removes names from the export list, and '-f' exports function names.
• name=value: This is the name of the variable and the value you want to assign to it.

Options in export Command in Linux

1. -p: This option displays a list of all names that are exported in the current shell.

   For example -

   Output:

   This command is useful to check the current exported environment variables and functions.

2. -n: This option removes the export property from each NAME.

   For example -

   Output:

   This command removes VARIABLE from the list of exported variables.

3. -f: The -f option means the NAMES refer to functions.

   For example -

   Output:

   This command exports a function called 'function_name'.

Example Usages

• Setting a new environment variable:

  Output:

  Explanation: This command creates an environment variable called VARNAME and assigns the value "VALUE" to it.

• Exporting a function:

  Output:

  Explanation: This command exports a shell function called 'function_name' so it can be used in child processes.

Advanced Use Cases of export Command in Linux

• Exporting multiple variables at once:

  Output:

  Explanation: This command sets and exports multiple environment variables at once.

• Unsetting an exported function:

  Output:

  Explanation: This command removes the exported function 'function_name' from the list of exports, making it unavailable in child processes.

• Exporting variables from a file:

  Output:

  Explanation: This command reads and executes commands from file_name in the current shell environment, effectively exporting variables defined in the file.