How to search for questions (and their answers) about known problems similar to mines?
Before sending an email to the dar-support mailing-list, you are asked to first look in the already sent email if there your problem has not been yet exposed and solved. This will first for you the fastest way to get an answer to your problem, and for me a way to preserve time for development. But yes, there is now tones of emails to read to have a chance to find the answer to your problem. Hopefully, there is a search engine at gmane (see the dark green area at the bottom of the page). This search engine is available for all the mailing list archived at gmane used around dar.
