CS 210

PROJECT #5                              Due Date: Noon Tuesday 05/05/09


     This project gives students an introduction to network programming 
in GNU/Linux assembly language using the 'sockets' API, and to the task
of implementing a standard internet protocol, as described in an RFC.  


                           PROBLEM STATEMENT

     Design a 'standalone' assembly language program (i.e., one that is
not linked with any code in the standard C runtime libraries, but which
instead makes direct system-calls to the Linux kernel using 'syscall'),
which will contact an official government-approved server that can send
back the precise time, expressed in Coordinated Universal Time (UTC) as
described in the RFC-868 (Time Protocol) document available online. 

     The time-server application your program should contact is running
on a network host named 'time-nw.nist.gov' which is located in Seattle.
You can discover its IP-address for use by your client program by using 
the standard 'ping' command:

		     $ ping -c1 time-nw.nist.gov

The port-number to which this time-server listens is specified (as part 
of the official 'Time Protocol') in the RFC-868 document.  Be sure that
you keep in mind the fact that network byte-order is 'big-endian' while
our Intel x86 host's byte-order is 'little-endian'.  Thus the value you
receive from any network time-server will need to have the order of its 
bytes 'swapped' before you attempt to do any computations with it using
our Intel-based Linux machines.  

     Keep in mind also that Coordinated Universal Time is measured as a
number of seconds that have elapsed since Midnight, January 1, 1900, in
Greenwich, England.  So in order to show the correct time-of-day now in
Caliornia, you will have to adjust for the difference in time-zones.

 
			WHAT TO DISPLAY

     Your program should print a message showing the current time using
the following 24-hour clock format:

		   TIME NOW IS hh:mm:ss (PDT)

As an option (for extra credit), your program may also show the current 
date, using the following format as an example:

	TIME NOW IS 11:45:22 (PDT) on WED 22 APR 2009


Please use the filenames 'utc.s', 'utc.o', and 'utc' for your project's
source-file, object-file, and executable-file.  (Copy these three files 
into your '/submit' folder, at: '/home/submit/cs210/<yourfolder>' )
_______________________________________________________________________
Allan B. Cruse         University of San Francisco          Spring 2009