I find myself on a regular basis looking for various debconf variables to set before installing packages on Ubuntu. This is typically to not have to type in the answers on the various configuration screens or because I want to script an install of some package. If the package has never been installed before on that specific server then the debconf variables will not display. You can always login to another server where the package is installed to see the variables but I am going to start posting information for common packages here so others can easily find them when searching.
Earlier I was transferring some configuration files from an application on a Windows 7 computer to an application on a OSX Lion computer. The location of a file referenced in the configuration files had changed so I needed to update about a hundred different INI files with the new location. Doing this on OSX is very easy using perl as long as you get the syntax correct as it can be tricky if there are multiple quotes and or slashes. Below is a quick example of a perl command used to replace a single line of text in multiple files without having to modify each file individually.
To locate and replace a string of text in a file using use the below text.
shell# vi filename
Once in vi use the following:
That will replace any instance of string with new-string.