:help change.txt mentions 2- or 3- letter :substitute commands, such as
:sgn and so on. I am guessing that these
:s[xx] correspond to flags, but am not sure how to use them.
For example, I would think that
:%sg/foo/bar would substitute all matches of
foo, including multiple occurences on the same line. However, that commands gives me an error --- "trailing characters".
What is the appropriate syntax for