Emacs defines certain column numbers to be tab stops. These
are used as stopping points by <TAB> when inserting whitespace in
Text mode and related modes (see Indentation), and by commands
like M-i (see Indentation Commands). By default, tab stops
are located every 8 columns. These positions are stored in the
tab-stop-list, whose value is a list of column numbers
in increasing order.
Instead of customizing the variable
tab-stop-list directly, a
convenient way to view and set tab stops is via the command M-x
edit-tab-stops. This switches to a buffer containing a description
of the tab stop settings, which looks like this:
: : : : : : 0 1 2 3 4 0123456789012345678901234567890123456789012345678 To install changes, type C-c C-c
The first line contains a colon at each tab stop. The numbers on the next two lines are present just to indicate where the colons are.
You can edit this buffer to specify different tab stops by placing
colons on the desired columns. The buffer uses Overwrite mode
(see Minor Modes). When you are done, type C-c C-c to make
the new tab stops take effect. Normally, the new tab stop settings
apply to all buffers. However, if you have made the
tab-stop-list variable local to the buffer where you called
M-x edit-tab-stops (see Locals), then the new tab stop
settings apply only to that buffer. To save the tab stop settings for
future Emacs sessions, use the Customize interface to save the value
tab-stop-list (see Easy Customization).
Note that the tab stops discussed in this section have nothing to do with how tab characters are displayed in the buffer. Tab characters are always displayed as empty spaces extending to the next display tab stop. See Text Display.