Re: 23.0.50; Cannot run calculator on TTY

[martin rudalics]

> In the emacspeak environment, I've set header-line-format to
> either show just the buffer name or in case of things like my
> alsaplayer interface, to show the title of the song that is
> playing.
> In info mode,  I  use the default behavior of using the header
> line to show the node information.
>
> In general, the header-line is one of my more favorite features
> in newer emacsuns since it lets me squirrel away summary
> information in a
> manner that gets automatically updated.

Presently, `split-window' has a problem with mode/header lines and small
heights (presumably also with scroll-bars and fringes).  To check
whether all windows are large enough after splitting it must make an
assumption about the presence of these on the new window.  It currently
bases its judgments on the appearance of the window that shall be split.
This is obviously wrong in your calculator example: You probably have a
header line on the existing window and `split-window' assumes that you
want a header line for the calculator window too.

I'm not sure how `split-window' should handle this:

(1) Use worst-case assumptions (all windows get scroll-bars, header
    lines, ...).

(2) Use assumptions based on default values.

(3) Provide explicit (optional) parameters for `split-window-vertically'
    and `split-window-horizontally'.

(4) Have functions like `calculator' split the window first and
    adjust it afterwards (probably using `fit-window-to-buffer').