command.txt

a screen handling program to provide a flashing message. You will have to design a screen layout f

Assignment 3 for comp170/570, semester 1, 2007. Due 2/6/7


Specification
-------------

    Write a screen handling program to provide a flashing message.
    You will have to design a screen layout for where messages
    are placed on the screen. You will also have to consider
    when to delay the program in order to give the user time
    to read the messages. That is, the program will use the
    curses library, signals and the sleep function. 

Screen Layout and Program Operation
-----------------------------------

    The screen should look something like this:


          Flashing Message


          Set new flash time: 



    Run the program with the flash time and message on the command line:

    $ flash 2 "Flashing Message"

    The message should flash on and off every 2 seconds.

    The user may also change the flash time by entering a number 
    followed by <Enter>

    The program should run in an infinite loop getting a new flash time
    but while this is happening, the message continues to flash.

    The user terminates the program by <ctrl>C thus sending the
    SIGINT signal. The program should display a termination
    message and exit.

Modularity.
----------

flasher.h

    this file should contain #define screen coordinates for sections
    of your screen layout.
    For example 

    #define MESSAGE_ROW 6
    #define MESSAGE_COL 10

flasher.c

    this file should contain the function that 
    reads a new flash time from the screen.


main.c

    this file should contain the main function, which calls the function
    in flasher.c, and handler functions for SIGARLM and SIGINT.

makefile

    You will also need a makefile so that the make utility can be used
    to build the program.

Hints
-----

    You may need to use these functions from the curses library

    move
    mvprintf
    scanw
    refresh

    You may need to use this function from #include <stdlib.h>

    exit(0);

    You may need to use these functions from #include <signal.h>

    signal
    alarm

    Since you can't pass parameters to signal handling functions,
    declare the flashtime and message as global variables so that
    they can be accessed by any function in main.c