CMPSCI 197J: HW1

  NAME: ..........................................                                             DUE DATE: Jan 07, 1999
     
    A. Define in a sentence or two:                                                (5 points)
         
      1. Operating System:

      An operating system is the program that controls all the other parts of a computer system     - both the hardware and the software. Most importantly, it allows you to make use of the facilities provided by the system.

      2. Kernel:

      It is at the core of each UNIX system and is loaded in whenever the system is started up -  referred to as a boot of the system.

      3. Shell:
       Whenever you login to a Unix system you are placed in a   program called the shell.

      4. POSIX.2: StandardShell and Standard utilities.

      5. Open System:Handle incompatibilites vendors of h/w and s/w make a conscious decison to create     products which will work together.
       
       

    B. Who command                                                                        (20 points)
     
      1. What option would you give to who to display the run-level of the local system?

      who -r

      2.  Compare the functionality of who am i and whoami .

      Entering who am i or who am I displays  your  login  name,  terminal  name,  date  and  time  you logged in, and host.      Entering whoami displays your login name only.
       

      3.  Give 3 other commands which contain information related to the who command.
        date(1), init(8), login(1), mesg(1), su(1), users(1), whoami(1)
       

      4.  Suppose XYZ(2) was one of the related commands from the previous question. What does the number 2 in parenthesis stand for?(Hint: man is a UNIX command just like who  or ls. You want to find more info on man. Be patient.  You might have to scroll through a lot of  information to get to the answer.)
       section[suffix]
       Specifies  the section and optional suffix identifiers for the reference page. The section parameter is either a number (0-9)  or one  of  the  letters C, L, F, n, l, p, or o.  The numbers 1 to 8 are most common. You usually  specify  section to identify a reference page that has the same title as another reference page in a
      different section.