All of the great discussion on this list about editors has made me curious about the data structures used in the various Unix editors. I found a great discussion of this for sam in Rob Pike’s publication “The Text Editor sam.” I’d like to read similar discussions of the data structures for ed, em, ex/vi. If anyone has suggestions of references, they would be very welcome! Similarly, if there are any pointers to references on some other data structures in editors like TECO, QED and E, I’d welcome them as well. All the best, David ........... David C. Brock Director and Curator Software History Center Computer History Museum computerhistory.org/softwarehistory Email: dbrock@computerhistory.org Twitter: @dcbrock Skype: dcbrock 1401 N. Shoreline Blvd. Mountain View, CA 94943 (650) 810-1010 main (650) 810-1886 direct Pronouns: he, him, his