I did post in Newsgroups: comp.unix.shell and In article <52%7k.11072$N87.159@nlpi068.nbdc.sbc.com>, and <dstromberglists@gmail.com> many examples were given of the meaning of the double slashes, but none seem to match the special significance, whatever that may be, in Xorg.0.log. Maybe they have some special meaning.