Using Graphviz as a Low-cost Option to Facilitate the Understanding of Unix Process System Calls

Unix system calls to create and execute processes are usually hard to understand for novice students. Using graphics for visualizing the behaviour of these system calls can be useful both for the teacher to explain and for the students to understand them. The problem here is that there is no software specifically addressed to generate graphical representations of these kind of programs, and to develop it would be costly. Instead of developing a complete system to visualize programs that use Unix system calls, we turned to a "cheaper" alternative solution. In this paper we show how we have used the open source graphviz tool to develop a simple way of generating graphical representations of the behaviour of these system calls, thus facilitating the comprehension of this important part in the learning of the Unix operating system.