IT 244: Introduction to Linux/Unix

IT 244: Introduction to Linux/Unix
Class 4 Exercise

Try using & in a directory name
```
mkdir  abc&def
```
You should get an error message
Look at the results
```
ls
```
mkdir created an abc directory and then tried to execute the non-existent command def
Remove the abc directory
```
rmdir abc
```
Check that the abc directory is gone
```
ls
```
Use the backslash, \ , to continue a command onto the next line
```
echo foo \[Enter]
bar [Enter]
```
Do not type [Enter].

Instead hit the Enter key (or Return if you have a Mac).

There should be no space between the \ and the newline created by the Enter key.

The shell did not process what you entered on the first line after you pressed the Enter key for the first time, it just gave you a new line.

The backslash, \ , turned off the special meaning of the newline character.

Move to your home directory
```
cd
```
Make sure you are in your home directory
```
pwd
```
Run ls without options or arguments
```
ls
```
You see only the visible files in your home directory.
Look at the contents of your it244 directory
```
ls  it244
```
Look at all the files in your home directory
```
ls  -a
```
Get a long listing of all the files in your home directory
```
ls  -al
```
Notice that you can use more than one option at a time.

Go to your ex4 directory
```
cd  it244/ex/ex4
pwd
```
Create a test directory
```
mkdir  test
```
Make sure the directory was created
```
ls
```
Create a test2 directory
```
mkdir test2
```
Look at the contents of your current directory
```
ls
```
You should see the a new test2 directory.

Move to your test2 directory
```
cd  test2
```
Create some files in this directory
```
touch  foo  bar  bletch  gobble
```
touch will create a file if it doesn't already exist.

That is not its primary purpose, but we'll only be using it in this way for this class.
Perform a long listing of the contents of the test2 directory
```
ls  -l
```
The first entry after -rw-r--r-- for each file is a 1. This means the files are one byte long, essentially empty.

touch creates empty files.
Remove the file foo
```
rm foo
```
Look at the directory contents
```
ls
```
Remove bar and bletch
```
rm  bar  bletch
```
List the contents of your current directory
```
ls
```
You should only see the file gobble.
Remove a file using the -i option
```
rm  -i  gobble
```
Enter "y" when prompted.
Look at the contents of your current directory
```
ls
```
The directory should be empty.
Create some more empty files
```
touch  baloney  ham  cheese  turkey
```
Look at the directory contents
```
ls
```
You should see the files you just created.
Remove all files from your current directory
```
rm  *
```
Look at the directory contents
```
ls
```
The directory should be empty.

Make sure you are in your test2 directory
```
pwd
```
If not, go there.
Create some files
```
touch  red  blue  green  orange
```
Move back up to the ex4 directory
```
cd  ..
```
Make sure your are in the ex4 directoryl
```
pwd
```
Examine the contents of the test2 directory
```
ls test2
```
Try to remove the test2 directory using rmdir
```
rmdir test2
```
You should get an error message because the directory is not empty.
Look at the contents of your ex4 directory
```
ls
```
The test2 directory is still there.
Remove the files in test2
```
rm  test2/*
```
List the contents of test2
```
ls test2
```
The directory should be empty.
Remove the test2 directory
```
rmdir  test2
```
Examine the contents of your ex4 directory
```
ls
```
The test2 directory should be gone

Create a file
```
touch  foo
```
Copy a file
```
cp  foo  footoyou
```
Look at the contents of the directory
```
ls
```
Go to the test directory
```
cd test
```
Create some files in this directory
```
touch  foo  bar  bletch
```
Go back to the ex4 directory
```
cd ..
```
Make sure you are in the ex4 directory
```
pwd
```
Copy a directory
```
cp  -r  test  test3
```
Look at the contents of the ex4 directory
```
ls
```
You should see a new test3 directory.
Look at the contents of test3
```
ls  test3
```
It should be the same as test

Go into the test3 directory
```
cd  test3
```
Change the name of footoyou
```
mv  foo  foo_to_you
```
Examine the changes
```
ls
```
Move a file to another directory
```
mv foo_to_you ../test
```
Look at the contents of the current directory
```
ls
```
foo_to_you is no longer in your current directory.
Look at the contents of your test directory
```
ls ../test
```
foo_to_you has been moved to the test directory.

Exit from your script session
```
exit
```
You need to do this or the typescript file will never be created.
Look at the contents of the typescript file
```
cat  typescript
```

If you want to run my text script on your Class Exercise script do the following
Run ex04.sh on your script
```
~ghoffman/it244_test/ex04.sh
```
The script will prompt you for your Unix username.