Figure out what buffers have been opened by a function in elisp?

Question

I'm trying to write a plugin that calls a function (icalendar-import-file) which has the nasty side effect of opening between 1 and 3 buffers every time it is called, and sometimes I want to call it a whole bunch of times.

I can't even find a function that will list buffers without popping up a new buffer, which is a little frustrating.

As far as I can tell that defun (ical...) doesn't return anything useful, so the two obvious solutions to me are to either: (1) set a variable to a list of buffers before I run the function, and then sweep through the buffers that exist after the function exits and delete the new ones, (something like save-excursion, but for buffers) or (2) somehow suppress the creation. It looks like ical... is pretty heavily dependent on this, though, so I'm not sure that that's feasible.

Answer 1

Are you looking for the function :

buffer-list is a built-in function in `C source code'.

(buffer-list &optional FRAME)

Return a list of all existing live buffers. If the optional arg FRAME is a frame, we return the buffer list in the proper order for that frame: the buffers in FRAME's `buffer-list' frame parameter come first, followed by the rest of the buffers.

Answer 2

If you know which function is creating the unwanted buffers, and understand what effect removing them will have, you could always advise them (using after advice) to remove the unwanted buffer right at the source of the problem. I think this is safer than simply removing any new buffer once a function has finished.