Lab0
====

Part A
-------
rndpassword is a command-line front-end to a random password generator.
rndpassword's man page is given in the Normal Behaviour section below.

Your task is  to implement the normal behaviour component of rndpassword
using passClient.pl as a starting point.

rndpassword (version 0.1)

Normal Behaviour
++++++++++++++++

Usage:
    rndpassword [-v] [-t <type>] [-n <length>]

     Options:
        -v  version 
        -t  set character type (default: num)
        -n  set length (default: 8 byte)

     Types:       (output sample)
        alnum     0xaVbi3O2Lz8E69s    # 0..9 a..z A..Z
        num       12378654            # 0..9 

     Examples:
        shell> rndpassword <CR>
        Password: 01234567
        shell>
         
        shell> rndpassword -n 16 <CR>
        Password: 0123456789012345
        shell>
     
        shell> rndpassword -t alnum  -n 4 <CR>
        Password: abcd
        shell>

        shell> rndpassword -v <CR>
        Version: 0.1
        Password: 01234567
        shell>

        shell> rndpassword  -n 3 -v <CR>
        Version: 0.1
        Password: 012
        shell>

        shell> rndpassword  -n 3 -v  -n 4 <CR>
        Version: 0.1
        Password: 0123
        shell>

Assumptions
+++++++++++
Command line arguments are separated into tokens by white space.

Command line arguments are processed left to right.

Switch parameters are found immediately following the switch.

Switches may appear multiple times on the command line.

Passwords are generated by a password server (see passServer.pl
for programmer interface).

The -v switch results in the immediate output of the version number.
All the  -n and -l switches (processed left to right) are used to
determine the parameters sent to the password server  (assuming no
exception).

An exception results in the immediate output of an error message
and the termination of rndpassword.

Exceptions
++++++++++
If a connection to the  password server is refused then output (on a
new line) "Error: Unable to Connect To Password Server\n".

If a switch is provided on the command line then its value must be an
element of {-v, -t, -n} else output (on a new line) "Error: Invalid
Switch\n".

If  -t is provided on the command line then the next token must be an
element of {num, alnum} else output (on a new line) "Error: Invalid
Type\n".

If  -n is provided on the command line then the next token must be an
integer in the range [2..64]  else output (on a new line) "Error: Invalid
Length\n".

Part B
------
With regard to the specification trichotomy, develop a specification
for passServer.pl (either version).

Deliverables
------------
1. Demonstrate the execution of rndpassword from the command line.

2. A print-out of your specification of passServer.pl.