Tags Tables for Info Files
==========================
You can speed up the access to nodes of a large Info file by giving
it a tags table. Unlike the tags table for a program, the tags table
for an Info file lives inside the file itself and is used automatically
whenever Info reads in the file.
To make a tags table, go to a node in the file using Emacs Info mode
and type `M-x Info-tagify'. Then you must use `C-x C-s' to save the
file. Info files produced by the `makeinfo' command that is part of
the Texinfo package always have tags tables to begin with.
Once the Info file has a tags table, you must make certain it is up
to date. If you edit an Info file directly (as opposed to editing its
Texinfo source), and, as a result of deletion of text, any node moves
back more than a thousand characters in the file from the position
recorded in the tags table, Info will no longer be able to find that
node. To update the tags table, use the `Info-tagify' command again.
An Info file tags table appears at the end of the file and looks like
this:
^_^L
Tag Table:
File: info, Node: Cross-refs^?21419
File: info, Node: Tags^?22145
^_
End Tag Table
Note that it contains one line per node, and this line contains the
beginning of the node's header (ending just after the node name), a
`DEL' character, and the character position in the file of the
beginning of the node.