Introduction to Unix
Homework 6


1. In the study guide, you will find a file called tartest.tar.  Download
   this file into your Linux environment.  If you are using an ssh client
   from a Windows computer, you may need to use `wget` or winscp (Windows
   program) to get the file into Linux.  Display the table of content of the
   file.  Extract the contents of the tartest.tar file (use the verbose
   option to tar).  Create a new tar file with the same directory tree as
   what was extracted from tartest.tar.  Use the gzip program to compress
   the tar file you just created.  Show your session.  

2. What are the inode numbers of the following files and directories on your
   system: / (root of the filesystem), your home directory, /etc/passwd,
   /usr/include, and /usr/share/man? Hint: use the `-d` option to `ls` to
   display directory entries rather than the contents of the directories.
   Show your session.

3. Create a symbolic link from your home directory to /etc/passwd and to
   /usr/bin.  Create a hard link to another file in your home directory.
   Use the ``ls -il`` command to display the symbolic and hard link files.
   Show your session.

4. Create a file which includes some text, some lines that begin with a spaces
   and or tabs and some blank lines.  Refer to the notes in the study guide
   related to how to use `sed`. Use the `sed` program with appropriate
   commands to display the file in the following ways: 

    a. any tabs or spaces removed from the beginning of lines. Hint: the
    regular expression `[ \t]*` means zero or more tab or space, `^` means
    beginning of line.

    b. any blank lines deleted.  Additional hint: $ means end of line.
    So the regular expression `^[ \t]*$` will catch any lines that
    completely blank or that only contain tabs or spaces (no other
    characters).

    c. Combine part a and part b to one `sed` command.  So delete blank
    lines and also delete any space or tab characters at the beginning of
    files.