Bookmarks are somewhat like registers in that they record positions you can jump to. Unlike registers, they have long names, and they persist automatically from one Emacs session to the next. The prototypical use of bookmarks is to record "where you were reading" in various files.
The prototypical use for bookmarks is to record one current position in each of several files. So the command C-x r m, which sets a bookmark, uses the visited file name as the default for the bookmark name. If you name each bookmark after the file it points to, then you can conveniently revisit any of those files with C-x r b, and move to the position of the bookmark at the same time.
To display a list of all your bookmarks in a separate buffer, type
C-x r l (
list-bookmarks). If you switch to that buffer,
you can use it to edit your bookmark definitions or annotate the
bookmarks. Type C-h m in that buffer for more information about
its special editing commands.
When you kill Emacs, Emacs offers to save your bookmark values in your default bookmark file, `~/.emacs.bmk', if you have changed any bookmark values. You can also save the bookmarks at any time with the M-x bookmark-save command. The bookmark commands load your default bookmark file automatically. This saving and loading is how bookmarks persist from one Emacs session to the next.
If you set the variable
bookmark-save-flag to 1, then each
command that sets a bookmark will also save your bookmarks; this way,
you don't lose any bookmark values even if Emacs crashes. (The value,
if a number, says how many bookmark modifications should go by between
Bookmark position values are saved with surrounding context, so that
bookmark-jump can find the proper position even if the file is
modified slightly. The variable
bookmark-search-size says how
many characters of context to record, on each side of the bookmark's
Here are some additional commands for working with bookmarks:
bookmark-write, to work with other files of bookmark values in addition to your default bookmark file.
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