11.4 The Mark Ring

Each buffer remembers previous locations of the mark, in the mark ring . Commands that set the mark also push the old mark onto this ring. One of the uses of the mark ring is to remember spots that you may want to go back to.

C-<SPC> C-<SPC> Set the mark, pushing it onto the mark ring, without activating it.

C-u C-<SPC> Move point to where the mark was, and restore the mark from the ring of former marks.

The command C-<SPC> C-<SPC> is handy when you want to use the mark to remember a position to which you may wish to return. It pushes the current point onto the mark ring, without activating the mark (which would cause Emacs to highlight the region). This is actually two consecutive invocations of C-<SPC> ( set-mark-command ); the first C-<SPC> sets the mark, and the second C-<SPC> deactivates it. (When Transient Mark mode is off, C-<SPC> C-<SPC> instead activates Transient Mark mode temporarily; see Disabled Transient Mark.)

To return to a marked position, use set-mark-command with a prefix argument: C-u C-<SPC> . This moves point to where the mark was, and deactivates the mark if it was active. Each subsequent C-u C-<SPC> jumps to a prior position stored in the mark ring. The positions you move through in this way are not lost; they go to the end of the ring.

If you set set-mark-command-repeat-pop to non- nil , then immediately after you type C-u C-<SPC> , you can type C-<SPC> instead of C-u C-<SPC> to cycle through the mark ring. By default, set-mark-command-repeat-pop is nil .

Each buffer has its own mark ring. All editing commands use the current buffer's mark ring. In particular, C-u C-<SPC> always stays in the same buffer.

The variable mark-ring-max specifies the maximum number of entries to keep in the mark ring. This defaults to 16 entries. If that many entries exist and another one is pushed, the earliest one in the list is discarded. Repeating C-u C-<SPC> cycles through the positions currently in the ring.

If you want to move back to the same place over and over, the mark ring may not be convenient enough. If so, you can record the position in a register for later retrieval (see Saving Positions in Registers).