### Switch to another version control backend (C-x v b)

Source: https://ftp.gnu.org/old-gnu/Manuals/emacs-21.2/html_mono/emacs.html

Use C-x v b to cycle through all backends the current file is registered under. With a prefix argument, it prompts for the backend to use in the minibuffer.

```emacs-lisp
C-x v b
```

--------------------------------

### Lisp comment indentation example

Source: https://ftp.gnu.org/old-gnu/Manuals/emacs-21.2/html_mono/emacs.html

Shows Emacs Lisp comment indentation conventions: comments starting with two semicolons are indented as code, while three semicolons start at the left margin. The example includes a function definition with mixed comment styles.

```lisp
;; This function is just an example
;;; Here either two or three semicolons are appropriate.
(defun foo (x)
;;; And now, the first part of the function:
  ;; The following line adds one.
  (1+ x))           ; This line adds one.

```

--------------------------------

### Inserted header text example

Source: https://ftp.gnu.org/old-gnu/Manuals/emacs-21.2/html_mono/emacs.html

Example of the text inserted when the default vc-static-header-alist matches a buffer name. Note that the text starts with a blank line.

```c
#ifndef lint
static char vcid[] = "string";
#endif /* lint */
```

--------------------------------

### Example first line with Lisp mode and variables

Source: https://ftp.gnu.org/old-gnu/Manuals/emacs-21.2/html_mono/emacs.html

Example of a first line specifying Lisp mode and setting fill-column and comment-column to numeric values.

```lisp
;; -*- mode: Lisp; fill-column: 75; comment-column: 50; -*-
```

--------------------------------

### Custom daylight savings start on October 1

Source: https://ftp.gnu.org/old-gnu/Manuals/emacs-21.2/html_mono/emacs.html

Lisp expression to set `calendar-daylight-savings-starts` to October 1 of the year, as an example of a custom rule.

```lisp
(list 10 1 year)
```

--------------------------------

### Example log entries before grouping

Source: https://ftp.gnu.org/old-gnu/Manuals/emacs-21.2/html_mono/emacs.html

Shows three log entries for different files that are checked in by the same author at nearly the same time and have the same text for two of them.

```plaintext
* For `vc.texinfo': `Fix expansion typos.'
* For `vc.el': `Don't call expand-file-name.'
* For `vc-hooks.el': `Don't call expand-file-name.'

```

--------------------------------

### Local variables list example

Source: https://ftp.gnu.org/old-gnu/Manuals/emacs-21.2/html_mono/emacs.html

Example of a local variables list with prefix ';;; ' and suffix '***'. The mode variable should be first, and values are used literally.

```lisp
;;; Local Variables: ***
;;; mode:lisp ***
;;; comment-column:0 ***
;;; comment-start: ";;; "  ***
;;; comment-end:"***" ***
;;; End: ***
```

--------------------------------

### To field with continuation line

Source: https://ftp.gnu.org/old-gnu/Manuals/emacs-21.2/html_mono/emacs.html

Example of a To header field with a continuation line, showing multiple addresses separated by commas and a continuation line starting with whitespace.

```text
To: foo@here.net, this@there.net,
  me@gnu.cambridge.mass.usa.earth.spiral3281
```

--------------------------------

### Enable Desktop in .emacs

Source: https://ftp.gnu.org/old-gnu/Manuals/emacs-21.2/html_mono/emacs.html

Add these lines at the end of your .emacs file to enable the Desktop library. This is an alternative to setting desktop-enable via the Customization buffer.

```emacs-lisp
(desktop-load-default)
(desktop-read)
```

--------------------------------

### Example log entries with clumping labels

Source: https://ftp.gnu.org/old-gnu/Manuals/emacs-21.2/html_mono/emacs.html

Shows log entries that start with a label of the form '{clumpname} ' to be clumped together without an intervening blank line.

```plaintext
* For `vc.texinfo': `{expand} Fix expansion typos.'
* For `vc.el': `{expand} Don't call expand-file-name.'
* For `vc-hooks.el': `{expand} Don't call expand-file-name.'

```

--------------------------------

### Specify font with -fn command-line option

Source: https://ftp.gnu.org/old-gnu/Manuals/emacs-21.2/html_mono/emacs.html

Use this command to start Emacs with a specific font, using a wildcard pattern for the font name. The example specifies the font with nickname '6x13'.

```shell
emacs -fn "-misc-fixed-medium-r-semicondensed--13-*-*-*-c-60-iso8859-1" &
```

--------------------------------

### X server font installation commands

Source: https://ftp.gnu.org/old-gnu/Manuals/emacs-21.2/html_mono/emacs.html

Commands to inform the X server about newly installed fonts. Run these after installing fonts to make them available.

```shell
 xset fp+ /usr/local/share/emacs/fonts
 xset fp rehash
```