The utility that will be developed in this section will read multiple log files and will create a graphical image with as many bars as the number of log files read. Each bar will represent the number of times a given IP address has been found in a log file.
However, the Unix philosophy tells us that instead of developing a single utility, we should make two distinct utilities: one for processing the log files and creating a report and another for plotting the data generated by the first utility: the two utilities will communicate using Unix pipes. Although this section will implement the first approach, you will see the implementation of the second approach later in The plotIP.go utility revisited section of this chapter.
The idea for the presented utility came from a tutorial that I wrote for a magazine where I developed a small Go program that did some plotting...