The goal of developing and supporting this parser script, is to help analyzing the log files mainainned by the FreeRADIUS daemon
radiusd (the content of those files is in plain text). When analyzing those files, the script is parsing their content line by line, and conditionally performing an additional check, if the line content has pattern mathching the one typical for the WiFi clients' autnetnication requests. That additional check has a goal to check if the MAC address of the client's WiFi adaper matches the one passed to the script as an invoking parameter. If match is found, the script prints the line to the standard output.
You can get the code of the script and more information at: