Changes in version 1.17:

The commands 'q' and 'Q' now work in a global command.
(Reported by J. A. Harris).

The new option '-E, --extended-regexp' has been added. It tells ed to use
extended regular expressions instead of the basic regular expressions
mandated by POSIX. (Suggested by Shawn Wagner).

Print the file name in case of read or write error. (Reported by Dan Jacobson).
