Thanks for the fast reply. On ver. 23.3 the function docs are these:
"
occur is an interactive compiled Lisp function in `replace.el'.
It is bound to M-s o.
(occur REGEXP &optional NLINES)
Show all lines in the current buffer containing a match for REGEXP.
This function can not handle matches that span more than one line.
Each line is displayed with NLINES lines before and after, or -NLINES
before if NLINES is negative.
NLINES defaults to `list-matching-lines-default-context-lines'.
Interactively it is the prefix arg.
The lines are shown in a buffer named `*Occur*'.
It serves as a menu to find any of the occurrences in this buffer.
C-h m in that buffer will explain how.
If REGEXP contains upper case characters (excluding those preceded by `\')
and `search-upper-case' is non-nil, the matching is case-sensitive.
"
In general I use Emacs for general text manipulation, not programming,
so, no, I'm not trying to get function names. Anyway, that code from
emacwiki seems to work and I can toggle-read-only on the buffer and use
rectangle to extract the matches only.
Ed