Part-1

1. How can you perform a ?oating point comparison? You should include two examples, one in C-shell and one in Bourne shell.

2 Explain the getopts command and write a sample shell script that uses getopts.

Part-2 Bourne Shell

1. You should write the following questions in Bourne shell and design suitable functions for each of them.

-  Write an alarm clock script that sleeps for a number of seconds and then beeps and displays a message after that times has elapsed. The number of seconds is set based on an input argument.

- Use a recursive function to print each argument passed to the function, regardless of how many arguments are passed. You are allowed to echo only the ?rst positional argument (echo $1).

2. Write a Bourne shell script that create an HTML ?le. This ?le should have a table of 4 columns and n rows. The table's elements are the contents of a directory. Directory names are written in blue and ordinary ?le names are written in green.

The above command line creates an html ?le myhtml.html and this ?le is shown in ?gure 1.

3. Write a Bourne shell program that displays the following menu to the user:

Would you like to:

1. Look someone up

2. Add someone to the phone book

3. Remove someone form the phone book

4. Quit

Please select one of the above (1-4):

For option 3, if multiple entries are found, then the program will prompt the user for the entry to be removed:

More than one match, please select the one to remove:

AAA Brown Remove[y or n]: y

AAA Blue Remove[y or no]: n

Part-3 Bourne shell and C-Shell

You should write two scripts for each of the following questions: one in Bourne shell and one in C-Shell.

1 Write a program called isyes that returns an exit status of 0 if its argument is "yes" and 1 otherwise. For purpose of this exercise, consider y,yes, Yes, YES and Y to be valid "yes" arguments.

2 Write a program called counttime that prints the number of hours and minutes that a user has been logged on to the system (assume that this is less than 24 hours). The name of the user is an input argument.

3 Write a Shell script that checks the validity of a userid that is passed as an input argument. If the userid is available on mars it will display the appropriate message.

4 Write a shell script that looks at the name on on the command line and responds with the output string Web page if the name ends with html or with htm and with the output string applet if the name ends with class

5 Write a shell script that changes the permissions of all the ?les in the current directories that ends with scpt so that they are executable by everyone.