Readers And Writers On WWW pages

After viewing vote to us!
(see bottom of the page)

Introduction

The problem of readers and writers is a problem with access to a resource. Writers are processes which use the resource individually. Readers may use it simultanously.

The problem solution without starving any of these two groups is based on following rules. The last reader leaving the reading room gives access to the first waiting writer (if there is any). The leaving writer lets all the waiting readers in. The new readers may also enter later only if there is no waiting writer.

Program

In our project the rading room is a resource controlled by a program called server. If the computer on which it is running has been shut down, you must run the program again. The simulation may by performed only if the server is running. Then readers and writers may be sent to the system. All of these, as well as watching the reading room state may be done using a WWW browser.

The simulation may be also performed in text mode on a Unix system; you can then view all the changes in the system immediately. When watching with a WWW browser there is always a delay depending on the connection with server.

Symbols

Specification

The reader, writer, and reading room programs are written in C taking advantage of message queues. The CGI (Common Gateway Interface) scripts creating interactive WWW pages (browsing the reading room, sending reader and writer) - in Perl (Practical Extraction & Report Language). The animated pictures are made with the GIF Construction Set program. The sources of this project may be downloaded here.

Links

Links to others pages related with this one may be found here.

[Run server] [Add reader] [Add writer] [Browse reading room] [Sources] [Links]
 

Competition

This page takes part in the competition "Notatki w Internecie" (Notes in Internet). If you liked it, you may vote to it. Just click the link below. The information about this competition may be found on the page http://galaxy.uci.agh.edu.pl/~konkurs/regulamin.html.

I liked this page, I vote!!!

We suggest you to vote when leaving the page. The later you vote the more points we get!