how to set variables interactively for ediff

Question

I'm using ediff mode, and I'd like to split the windows horizontally instead of the vertical default. The ediff manual says this can be done interactively.

ediff-split-window-function

Controls the way you want the window be split between file-A and file-B (and file-C, if applicable). It defaults to the vertical split (split-window-vertically, but you can set it to split-window-horizontally, if you so wish. Ediff also lets you switch from vertical to horizontal split and back interactively.

Note that if Ediff detects that all the buffers it compares are displayed in separate frames, it assumes that the user wants them to be so displayed and stops splitting windows. Instead, it arranges for each buffer to be displayed in a separate frame. You can switch to the one-frame mode by hiding one of the buffers A/B/C.

You can also swap the windows where buffers are displayed by typing ~

I've tried using M-x set-variable to set this variable to split-window-horiztonally, but that did not change the layout. I want to do this interactively, I know I can set it as default in .emacs but I dont want to do that at this stage.

Answer 1

I want to do this interactively, I know I can set it as default in .emacs but I dont want to do that at this stage.

Type |

(n.b. that's the | pipe character; as opposed to I or l or 1.)

You should probably also type ? and review the information it shows you.