The `dir' File
==============

  For Info to work, the `info' directory must contain a file that
serves as a top level directory for the Info system.  By convention,
this file is called `dir'.  (You can find the location of this file
within Emacs by typing `C-h i' to enter Info and then typing `C-x C-f'
to see the pathname to the `info' directory.)

  The `dir' file is itself an Info file.  It contains the top level
menu for all the Info files in the system.  The menu looks like this:

     * Menu:
     
     * Info:    (info).     Documentation browsing system.
     * Emacs:   (emacs).    The extensible, self-documenting
                            text editor.
     * Texinfo: (texinfo).  With one source file, make
                            either a printed manual using
                            TeX or an Info file.
     ...

  Each of these menu entries points to the `Top' node of the Info file
that is named in parentheses.  (The menu entry does not need to specify
the `Top' node, since Info goes to the `Top' node if no node name is
mentioned.  See Nodes in Other Info Files: Other Info Files.)

  Thus, the `Info' entry points to the `Top' node of the `info' file
and the `Emacs' entry points to the `Top' node of the `emacs' file.

  In each of the Info files, the `Up' pointer of the `Top' node refers
back to the `dir' file.  For example, the line for the `Top' node of
the Emacs manual looks like this in Info:

     File: emacs  Node: Top, Up: (DIR), Next: Distrib

(Note that in this case, the `dir' file name is written in upper case
letters--it can be written in either upper or lower case.  Info has a
feature that it will change the case of the file name to lower case if
it cannot find the name as written.)