This is the first programming task for course Advanced Operating Systems.
Authors: 
-Ediber Montoya Moreira
-Leandro Cordero

The specification could be found in file Proyecto1.pdf.


Steps to build the project for the first time:
1- Execute ./autogen.sh script
2- Execute ./configure
3- Execute ./make

You have additional make options:
- make clean: Remove any generated file
- make install: Install the executable
- make uninstall: Uninstall de executable

Note: install and uninstall must be run as root (sudo make ...)

This application reads the configuration from file "config.txt"
that should be located in the executable directory. The first line in this file
should contain two integer values: The first, is the value indicating whether
we use preemptive schedulling or not, and the second one is the time slice for
each process to run or the work factor to perform for each thread before
releasing the processor. The subsequent lines in the file represents threads
configuration. In this lines, the first value indicates de tickets assigned to
this thread and the second is the total work to perform for this thread.
Here is a config file example:
config.txt
1 150
50 20
10 50
32 25
100 50
50 20

In this case we use a preemptive schedulling with a quantum of 150 ms. 

Calculations:
-------------
For calculating 2 arccos(0) we use that arccos(x) = (PI/2) - arcsin(x) for x = 0.
So 2 arccos(0) = 2 * (PI/2) = PI;
In order to aproximate PI we use that arctan(1) = PI/4 so:
PI = 4 * arctan(1).

arctan(1) = 1 - 1/3 + 1/5 - 1/7 + 1/9 - 1/11 ... + (((-1)^n)/(2n + 1))
see:
http://www.intmath.com/series-expansion/2-maclaurin-series.php
http://en.wikipedia.org/wiki/Leibniz_formula_for_pi

This approach is known for its slow convergence but it serves the purpose in
this exercise