If we want to create our own library of functions, then we can create a script and add all the functions into this script. We can make all the functions from our script functions.sh available in the current shell by calling source or the period . command.
The procedure to load all functions into the current shell is as follows:
$ countryUSA
Since the function country is not a part of the shell environment, this command will give an error:
$ . functions.sh
Or:
$ source functions.sh $ country USA India Japan
This will execute the function country along with the parameter USAIndia Japan.
We can even load a script containing library functions inside another script as follows:
#!/bin/bash . /../my-library.sh call_library_functions();
We have called the library function script my-library.sh inside another script. This will define all the functions within the script my-library.sh available in the current script environment.