IT 244: Introduction to Linux/Unix

IT 244: Introduction to Linux/Unix
Homework 9

All this work should be done on users3.cs.umb.edu

Modifications to .bash_profile in your home directory.
30 points
A file named hw9.sh that contains the commands you would type at the command line to achieve each of the steps listed below.
This file should be in an hw9 directory inside your hw directory inside your it244 directory.
You must make your script executable. 70 points

Create an hw9 directory in your hw directory inside your it244 directory
Go to the hw9 directory and run Unix commands that will execute the steps below
When you have a command line that does what the step asks you to do, paste it into hw9.sh using nano or any other text editor
When you have completed all the steps, create an echo statement before the commands for each step, that will print the step number to the terminal

The script hw9.sh must have the format specified in this document
Scripts that do not follow the rules specified in the document mentioned above will will have points deducted from their score
Be sure to test your script and correct any errors you find
You will lose 5 points for each error that occurs when running your script
To run your script and see only the error messages run the following command
```
./hw9.sh  >  /dev/null
```

Go to your home directory and edit .bash_profile to define the global variable omar whose value is the absolute pathname of my home directory.
Again in .bash_profile define an alias ts which will take you to my home directory using the variable defined above.
Also in .bash_profile define a function go_show, that will
- Go to a specific directory
- Print your current location
- Print the contents of your current directory
The directory this function takes you to will be specified as an argument to the function on the command line. You will need to use a positional parameter to do this.

Print to the terminal the value of the variable omar.
Using a pipeline, grep and a command that will show all your global variables, print to the screen the full definition of the variable omar. Do not use echo to do this. The command to show all global variables was mentioned in the first class were global variables were discussed.
Aliases and functions are not global, so they cannot normally be run inside a shell script.
- Go to your home directory
- Run a command that will run the startup file where you defined the alias ts and the function go_show inside your current shell
- Run a command that will show the definition of the function go_show
Go to your home directory.
Use the function go_show to move to my home directory using the global variable omar.
Run a command that will show all the aliases you have currently defined.
Run a command that will show the last 20 commands in your history list.
Create the variable omar_home whose value is the following
```
The home directory of my instructor is /home/tsoro
```
When you define this variable, it must use the value of the variable omar.
Now print the value of omar_home to the terminal.