Creating reference files

The procedures in the following sections involve getting file attributes and checking those attributes for any suspicious settings. The checking portion of the work can be considerably simplified if you execute these procedures and save the results in a reference file. Then, at a later time, when you execute one of these procedures again, you can compare the current output with the output of the reference file. The diff(1) command is a good way to compare two files. This will allow you to pinpoint any differences quickly and let you investigate them. As you install or remove files, you need to update your reference files.