Midterm

1. What do the following commands do ? Explain. 

$ date +%T
$ cat /etc/passwd > /dev/null
$ ln $HOME/abc /tmp/abc
$ cat /etc/passwd | rm
$ ls $HOME | cp /tmp
$ ls -a $HOME

2. Using find 

a. find all files from /usr/src that are owned by bin
b. find all files from the current directory that have inode number as 3000
c. find all files from /dev that are character special files. 

3. Write commands with options for the following

a. to duplicate the directory $HOME/homework to or as $HOME/project
b. to remove the whole directory $HOME/tmp
c. to copy the files "cpu" "chip" to /tmp directory from your home directory.

4. Write commands for the following using chmod. Do not use numbers

a. to set the permissions of the directory $HOME/ctmp to read only for user
read and write for group and no perms for other
b. to add read permissions to group and other for any file 

5. Write a command to create a symlink to $HOME/homework in /tmp
Explain what will happen after the operation, if the link file is removed.
Explain what will happen if $HOME/homework is removed. 

6.  In vi

a. How will you get the output of "ls -l /tmp" into a file when you are in a vi
session
b. How will you display where you are in the file ?
c. How will you use : mode to move your cursor forward 20 lines ?