Ex. 3 Defining functions in shell(4 Points)

In this exercise, you will update the script showusr that is given to you (you can use vi to edit this file), to write a function fname, that accepts a userid (such as your socs unix account) as the argument and sets an environment variable FNAME with the value that is the first name of the userid (explore the pinky command to get the first name of the userid). The function will also return an integer code to indicate its status (see examples below). Do not use the exit command in the function !

1.(1 Point) For properly commenting throughout the source code.

2.(1 Point) If fname is not passed an argument, set the variable FNAME to ERROR and return a value of 1. Below is an example of me loading the function to shell environment and then executing it (with no argument). I am using the echo command to check the return code as well as the value stored in FNAME.

3.(1 Point) if the argument passed to fname cannot be found among the sessions logged in, it should set FNAME to NOTFOUND and return 0.

4.(1 Point) if the userid passed as argument to fname is found among the sessions logged in, it should set FNAME to the first name of that user and return 0.

You should turn in your modified showusr script.