IT 244: Introduction to Linux/Unix

IT 244: Introduction to Linux/Unix
Class 6 Exercise

Go to the files directory for this course

cd  /home/ghoffman/course_files/it244_files

Examine the contents of numbers1.txt and numbers2.txt
```
cat  numbers1.txt
cat  numbers2.txt
```
Use diff to compare numbers1.txt and numbers2.txt
```
diff  numbers1.txt  numbers2.txt
```
The output is hard to read, because it contains instructions for the Unix patch utility to convert the first file given at the command line to the second.
Use the -y option to diff to create readable output
```
diff  -y  numbers1.txt  numbers2.txt
```
This output is much easier to read.

Make sure you are in your home directory
```
cd
```
Go to your ex6 directory
```
cd it244/ex/ex6
```
Make sure you are in your ex6 directory
```
pwd
```
Copy red_sox.txt to your ex6 directory
```
cp  /home/ghoffman/course_files/it244_files/red_sox.txt  .
```
Make sure you include the dot, ., or you will get an error message.
Make sure the copy operation worked
```
ls
```
Print the red_sox.txt
```
cat  red_sox.txt
```
Find all Red Sox wins
```
grep Win red_sox.txt 
```
Find all Red Sox wins at home
```
grep Win red_sox.txt | grep vs
```
Here, the first instance of grep is the source, and the second is a filter.
Find all Red Sox wins at home, sorted in reverse order by date
```
grep Win red_sox.txt | grep vs | sort -nr
```
This is a pipeline, with three separate processes, one for each command.

Show today's date
```
date
```
Use the formatting options of date to show today's date using the format YYYY-MM_DD
```
date +"%Y-%m-%d"
```

Find files associated with python3
```
whereis python3
```
Note that whereis reveals many more files.
Find files associated with tar
```
whereis tar
```

Use finger to see who else is connected to your current host
```
finger
```
Use finger on your own Unix username
```
finger YOUR_UNIX_USERNAME
```
In place of YOUR_UNIX_USERNAME, you must put your Unix username.
Run finger on the username "ghoffman"
```
finger ghoffman
```

Go to your ex6 directory
```
cd ~/it244/ex/ex6
```
Make sure you are in your ex6 directory
```
pwd
```
If not, see me.
Create the script ex6.sh
```
nano ex6.sh
```
Write into this file all the commands from the sections above

Copy all the commands from the sections diff up to and including finger.

Do not call nano inside your script.
Save this file

Save and quit.
Run this script looking for error messages
```
bash  ex6.sh > /dev/null
```
Running ex6.sh this way will only print error messages.

If you see nothing your script has no Unix errors.

If you find any errors, fix them.
Test your script
```
~ghoffman/it244_test/ex06.sh
```
When the script asks if you are ready for more, hit Return or Enter.