How to scroll line by line in GNU Emacs?

See some of the suggestions on the Emacs Wiki:

Emacs Wiki: Smooth Scrolling

(setq scroll-step            1
      scroll-conservatively  10000)

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If you want to position the screen exactly, you can use Ctrl-L.

By default it positions the current line in the middle of the screen.

ESC 0 Ctrl-L positions the current line at the top.

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I'm a bit late to the party, but if you don't mind installing a package then smooth-scrolling (github, also available in MELPA) may be what you're looking for - it certainly works for me.

Once you've installed it you can pop the following in your init.el:

(require 'smooth-scrolling)
(smooth-scrolling-mode 1)
(setq smooth-scroll-margin 5)

The last line is optional; it starts scrolling near the screen edge rather than at it, so you've always got a little context around the point. Adjust to taste.

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My solution is not to change Emac's default scrolling, but rather to create a key sequence command from a macro. This way you have a convenient way to scroll one line at a time when you want. Not ideal, but super easy. It just happens that M-(↓) and M-(↑) are available, so that's what I used.

This is how I did it. First, you need to record a macro for one line scrolls, up and down.

Begin macro

C-x ( 

Scroll down one

C-u 1 C-v

Stop macro

C-x )

For scroll up one, use

C-u 1 M-v

Next you need to name the macro.

M-x name-last-kbd-macro

Give it a name when prompted like:

down-one-line

Then just use the following to bind a key sequence to that command name:

M-x global-set-key

And upon prompting, use something like:

M-(down arrow)

Then it will ask you which command you want to bind, and you should give it the name you invented earlier, e.g., down-one-line.

Here is where I got this information. You can also find instructions below and elsewhere about adding your macro to the .emacs file.

Here for macro definition explanation

Here for how to control scrolling

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I've been using these in my .emacs file since 2000.

(global-set-key (quote [M-down]) (quote View-scroll-line-forward))
(global-set-key (quote [M-up]) (quote View-scroll-line-backward)) 

This way, I can keep the Emacs default behavior as well as scroll one line at a time, depending on what I'm doing.

This worked till at least GNU Emacs 22. I recently upgraded to Emacs 24 and discovered that View-scroll-line-forward and View-scroll-line-backward are no longer available. After some hunting, I discovered that scroll-up-line and scroll-down-line work. So if you're using Emacs 24, you can use this.

(global-set-key (quote [M-down]) (quote scroll-up-line))
(global-set-key (quote [M-up]) (quote scroll-down-line)) 

I mostly skipped Emacs 23, so if that is the version you're using, you can experiment with both the above.

Note: scroll-up-line actually scrolls one line down, because the buffer is being moved one line up.

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I rebind my arrow keys to perform scrolling operations.

(global-set-key [up] (lambda () (interactive) (scroll-down 1)))
(global-set-key [down] (lambda () (interactive) (scroll-up 1)))

(global-set-key [left] (lambda () (interactive) (scroll-right tab-width t)))
(global-set-key [right] (lambda () (interactive) (scroll-left tab-width t)))

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Simples do this:

(global-set-key [M-up] (lambda () (interactive) (scroll-up 1)))
(global-set-key [M-down] (lambda () (interactive) (scroll-down 1)))

then meta cursor up moves up and meta cursor down moves down.

QED. Not sure what all the above people were smoking!

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I have the following in my .emacs file to enable a nice ctrl-up, ctrl-down scrolling behavior. I also use this for the mousewheel.

(defun scroll-down-in-place (n)
  (interactive "p")
  (previous-line n)
  (scroll-down n))

(defun scroll-up-in-place (n)
  (interactive "p")
  (next-line n)
  (scroll-up n))

(global-set-key [mouse-4] 'scroll-down-in-place)
(global-set-key [mouse-5] 'scroll-up-in-place)
(global-set-key [C-up] 'scroll-down-in-place)
(global-set-key [C-down] 'scroll-up-in-place)

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If you are looking for a quick way to create a scroll-like effect, enter in C-n and C-l sequentially which moves the cursor down and then centers it.

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To have the "vim" scrolling put this to your .emacs file:

(defun next-line-and-recenter () (interactive) (next-line) (recenter))
(defun previous-line-and-recenter () (interactive) (previous-line) (recenter))
(global-set-key (kbd "C-n") 'next-line-and-recenter)
(global-set-key (kbd "C-p") 'previous-line-and-recenter)

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Since it can be annoying to use the M-up, M-down because it interferes with the org-mode which overloads these commands. To avoid this issue I personally use those commands which combine M-page-up M-page-down". Here I defined the scroll up and down to 1 line.

;;;scroll by `number-of-lines' without the cursor attached to the screen
(global-set-key [M-prior] (lambda () (interactive) (let ((number-of-lines 1))
                                                  (scroll-down number-of-lines)
                                                  (forward-line (- number-of-lines)))))
(global-set-key [M-next] (lambda () (interactive) (let ((number-of-lines 1))
                                                  (scroll-up number-of-lines)
                                                  (forward-line number-of-lines))))

;;;scroll by `number-of-lines' with the cursor attached to the screen
(global-set-key [S-M-prior] (lambda () (interactive) (let ((number-of-lines 1))
                                                  (scroll-down number-of-lines))))
(global-set-key [S-M-next] (lambda () (interactive) (let ((number-of-lines 1))
                                                  (scroll-up number-of-lines))))

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M-x customize-variable scroll-conservatively

Set it to 1.

You don't really want to do this, though.

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If you don't mind using the mouse and have a scroll wheel, you can customize the variable mouse-wheel-scroll-amount by either:

C-h v mouse-wheel-scroll-amount (click on customize, change value to "Specific # of lines" 1, ApplyAndSave.)

or add to .emacs the line: '(mouse-wheel-scroll-amount '(1 ((shift) . 1) ((meta)) ((control) . text-scale)))

There are lots of possibilities listed at https://www.emacswiki.org/emacs/Scrolling

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If you start emacs in .xsession, in my case setting scroll-conservatively to 100+ will not work, nor scroll-step 1. But if u start emacs after X, it works.

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After playing a bit with the available configuration (emacs 26.3), I got to the following set of values:

(setq scroll-step 1
      scroll-preserve-screen-position t
      scroll-margin 10
      scroll-conservatively 10
      maximum-scroll-margin 0.0
      scroll-up-aggressively 0.0
      scroll-down-aggressively 0.0)

I believe the values for scroll-margin and scroll-conservatively do not matter much because the maximum-scroll-margin clamps them down. They just need to be equal (maybe?).

Scroll happens line by line, even on the end of the file (worst case for me). The only missing feature was that with this the margin on top and bottom are lost.

Its a compromise and, for me, smooth scrolling is worth it.

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