Clog needs a rules file before it can do anything. If you run
before creating a rules file, you see this:
$ clog Cannot open /home/xxx/.clogrc See 'man clog' for details, and a sample file.
Clog allows you to specify a rules files on the command line, and if that doesn't exist, you get the same error:
$ clog -f asdf Cannot open asdf See 'man clog' for details, and a sample file.
Creating a rules file is as simple as creating an empty file:
$ touch ~/.clogrc $
Comments in the rule files begin with the '
so you can also create a rule file like this:
$ echo '# Clog Rules' > ~/.clogrc $
Examples of what should be in your rules files are discussed in subsequent documents.