go to the last line with "G"
and write the file with ":w".  You edit several other files, and then use
":edit one.txt" to come back to "one.txt".  If you now use `" Vim jumps to the
last line of the file.  Using `. takes you to the position where you deleted
the character.  Even when you move around in the file `" and `. will take you
to the remembered position.  At least until you make another change or leave
the file.


FILE MARKS

In section |03.10| was explained how you can place a mark in a file with "mx"
and jump to that position with "`x".  That works within one file.  If you edit
another file and place marks there, these are specific for that file.  Thus
each file has its own set of marks, they are local to the file.
   So far we were using marks with a lowercase letter.  There are also marks
with an uppercase letter.  These are global, they can be used from any file.
For example suppose that we are editing the file "foo.txt".  Go to halfway
down the file ("50%") and place the F mark there (F for foo): >

	50%mF

Now edit the file "bar.txt" and place the B mark (B for bar) at its last line:
>
	GmB

Now you can use the "'F" command to jump back to halfway of foo.txt.  Or edit
yet another file, type "'B" and you jump to the end of bar.txt.

The file marks are remembered until they are placed somewhere else.  Thus you
can place the mark, do hours of editing and still be able to jump back to that
mark.
   It's often useful to think of a simple connection between the mark letter
and where it is placed.  For example, use the H mark in a header file, M in
a Makefile and C in a C code file.

To see where a specific mark is, give an argument to the ":marks" command: >

	:marks M

You can also give several arguments: >

	:marks MCP

Don't forget that you can use CTRL-O and CTRL-I to jump to older and newer
positions without placing marks there.

==============================================================================
*07.4*	Backup files

Usually Vim does not produce a backup file.  If you want to have one, all you
need to do is execute the following command: >

	:set backup

The name of the backup file is the original file with a  ~  added to the end.
If your file is named data.txt, for example, the backup file name is
data.txt~.
   If you do not like the fact that the backup files end with ~, you can
change the extension: >

	:set backupext=.bak

This will use data.txt.bak instead of data.txt~.
   Another option that matters here is 'backupdir'.  It specifies where the
backup file is written.  The default, to write the backup in the same
directory as the original file, will mostly be the right thing.

	Note:
	When the 'backup' option isn't set but the 'writebackup' is, Vim will
	still create a backup file.  However, it is deleted as soon as writing
	the file was completed successfully.  This functions as a safety
	against losing your original file when writing fails in some way (disk
	full is the most common cause; being hit by lightning might be
	another, although less common).


KEEPING THE ORIGINAL FILE

If you are editing source files, you might want to keep the file before you
make any changes.  But the backup file will be overwritten each time you write
the file.  Thus it only contains the previous version, not the first one.
   To make Vim keep the original file, set the 'patchmode' option.  This
specifies the extension used for the first backup of a changed file.  Usually
you would do this: >

	:set patchmode=.orig

When you now edit the file data.txt for the first time, make changes and write
the file, Vim will keep a copy of the unchanged file under the name
"data.txt.orig".
   If you make further changes to the file, Vim will notice that
"data.txt.orig" already exists and leave it alone.  Further backup files will
then be called "data.txt~" (or whatever you specified with 'backupext').
   If you leave 'patchmode' empty (that is the default), the original file
will not be kept.

==============================================================================