Commit b457dbd9 authored by Eli Zaretskii's avatar Eli Zaretskii
Browse files

Update for Emacs 21. Add index entries.

parent db921254
\input texinfo @c -*-texinfo-*-
@comment %**start of header
@setfilename ../info/info
@settitle Info 1.0
@comment %**end of header
@dircategory Emacs
@comment %**start of header
@setfilename info.info
@settitle Info
@syncodeindex fn cp
@syncodeindex vr cp
@syncodeindex ky cp
@comment %**end of header
@comment $Id: info.texi,v 1.16 2001/02/03 13:00:56 karl Exp $
@dircategory Texinfo documentation system
@direntry
* Info: (info). Documentation browsing system.
* Info: (info). Documentation browsing system.
@end direntry
@iftex
@finalout
@end iftex
@ifinfo
This file describes how to use Info,
the on-line, menu-driven GNU documentation system.
This file describes how to use Info, the on-line, menu-driven GNU
documentation system.
Copyright (C) 1989, 1992 Free Software Foundation, Inc.
Copyright (C) 1989, 92, 96, 97, 98, 99, 2000, 2001
Free Software Foundation, Inc.
Permission is granted to copy, distribute and/or modify this document
......@@ -38,25 +39,19 @@ separately from the collection, you can do so by adding a copy of the
license to the document, as described in section 6 of the license.
@end ifinfo
@setchapternewpage odd
@titlepage
@sp 11
@center @titlefont{Info}
@sp 2
@center The
@sp 2
@center On-line, Menu-driven
@sp 2
@center GNU Documentation System
@title Info
@subtitle The online, hyper-text GNU documentation system
@author Brian Fox
@author and the GNU Texinfo community
@page
@vskip 0pt plus 1filll
Copyright @copyright{} 1989, 1992, 1993 Free Software Foundation, Inc.
Copyright @copyright{} 1989, 92, 93, 96, 97, 98, 99, 2000, 2001
Free Software Foundation, Inc.
@sp 2
Published by the Free Software Foundation @*
59 Temple Place, Suite 330 @*
Boston, MA 02111-1307 USA @*
59 Temple Place - Suite 330 @*
Boston, MA 02111-1307, USA.
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.1 or
......@@ -76,32 +71,27 @@ separately from the collection, you can do so by adding a copy of the
license to the document, as described in section 6 of the license.
@end titlepage
@paragraphindent 3
@ifinfo
@node Top, Getting Started, (dir), (dir)
@ifnottex
@node Top
@top Info: An Introduction
Info is a program for reading documentation, which you are using now.
To learn how to use Info, type the command @kbd{h}. It brings you
to a programmed instruction sequence. If at any time you are ready to
stop using Info, type @samp{q}.
@c Need to make sure that `Info-help' goes to the right node,
@c which is the first node of the first chapter. (It should.)
@c (Info-find-node "info"
@c (if (< (window-height) 23)
@c "Help-Small-Screen"
@c "Help")))
@ifinfo
If you are new to Info and want to learn how to use it, type the
command @kbd{h} now. It brings you to a programmed instruction
sequence.
To learn advanced Info commands, type @kbd{n} twice. This brings you to
@cite{Info for Experts}, skipping over the `Getting Started' chapter.
@end ifinfo
@end ifnottex
@menu
* Getting Started:: Getting started using an Info reader.
* Advanced Info:: Advanced commands within Info.
* Create an Info File:: How to make your own Info file.
* Creating an Info File:: How to make your own Info file.
* Index:: An Index of topics, commands, and variables.
@end menu
@node Getting Started, Advanced Info, Top, Top
......@@ -111,23 +101,26 @@ To learn advanced Info commands, type @kbd{n} twice. This brings you to
This first part of the Info manual describes how to get around inside
of Info. The second part of the manual describes various advanced
Info commands, and how to write an Info as distinct from a Texinfo
file. The third part is about how to generate Info files from
file. The third part briefly explains how to generate Info files from
Texinfo files.
@iftex
This manual is primarily designed for use on a computer, so that you can
try Info commands while reading about them. Reading it on paper is less
@ifnotinfo
This manual is primarily designed for browsing with an Info reader
program on a computer, so that you can try Info commands while reading
about them. Reading it on paper or with an HTML browser is less
effective, since you must take it on faith that the commands described
really do what the manual says. By all means go through this manual now
that you have it; but please try going through the on-line version as
well.
really do what the manual says. By all means go through this manual
now that you have it; but please try going through the on-line version
as well.
@cindex Info reader, how to invoke
@cindex entering Info
There are two ways of looking at the online version of this manual:
@enumerate
@item
Type @code{info} at your shell's command line. This approach uses a
stand-alone program designed just to read Info files.
small stand-alone program designed just to read Info files.
@item
Type @code{emacs} at the command line; then type @kbd{C-h i} (Control
......@@ -143,7 +136,7 @@ the screen.
@c Is it worth worrying about what-if the beginner goes to somebody
@c else's Emacs session, which already has an Info running in the middle
@c of something---in which case these simple instructions won't work?
@end iftex
@end ifnotinfo
@menu
* Help-Small-Screen:: Starting Info on a Small Screen
......@@ -155,33 +148,32 @@ the screen.
* Help-Q:: Quitting Info
@end menu
@node Help-Small-Screen, Help, , Getting Started
@comment node-name, next, previous, up
@node Help-Small-Screen
@section Starting Info on a Small Screen
@iftex
@ifnotinfo
(In Info, you only see this section if your terminal has a small
number of lines; most readers pass by it without seeing it.)
@end iftex
@end ifnotinfo
Since your terminal has an unusually small number of lines on its
@cindex small screen, moving around
Since your terminal has a relatively small number of lines on its
screen, it is necessary to give you special advice at the beginning.
If you see the text @samp{--All----} at near the bottom right corner
If you see the text @samp{--All----} near the bottom right corner
of the screen, it means the entire text you are looking at fits on the
screen. If you see @samp{--Top----} instead, it means that there is
more text below that does not fit. To move forward through the text
and see another screen full, press the Space bar, @key{SPC}. To move
back up, press the key labeled @samp{Delete} or @key{DEL}.
and see another screen full, press @key{SPC}, the Space bar. To move
back up, press the key labeled @samp{Backspace} or @samp{DEL} (on some
keyboards, this key might be labeled @samp{Delete}).
@ifinfo
Here are 40 lines of junk, so you can try Spaces and Deletes and
Here are 40 lines of junk, so you can try Spaces and DEL and
see what they do. At the end are instructions of what you should do
next.
@format
This is line 17
This is line 18
This is line 19
This is line 20
This is line 21
This is line 22
......@@ -219,10 +211,14 @@ This is line 53
This is line 54
This is line 55
This is line 56
This is line 57
This is line 58
This is line 59
@end format
If you have managed to get here, go back to the beginning with
Delete, and come back here again, then you understand Space and
Delete. So now type an @kbd{n} ---just one character; don't type
@kbd{DEL}, and come back here again, then you understand Space and
DEL. So now type an @kbd{n} ---just one character; don't type
the quotes and don't type the Return key afterward--- to
get to the normal start of the course.
@end ifinfo
......@@ -233,44 +229,60 @@ get to the normal start of the course.
You are talking to the program Info, for reading documentation.
@cindex node, in Info documents
Right now you are looking at one @dfn{Node} of Information.
A node contains text describing a specific topic at a specific
level of detail. This node's topic is ``how to use Info''.
level of detail. This node's topic is ``how to use Info''. The mode
line says that this is node @samp{Help} in the file @file{info}.
@cindex header of Info node
The top line of a node is its @dfn{header}. This node's header (look at
it now) says that it is the node named @samp{Help} in the file
@file{info}. It says that the @samp{Next} node after this one is the node
it now) says that the @samp{Next} node after this one is the node
called @samp{Help-P}. An advanced Info command lets you go to any node
whose name you know.
whose name you know. In the stand-alone Info reader program, the
header line shows the names of this node and the info file as well.
In Emacs, the header line is displayed in a special typeface, and it
doesn't scroll off the screen when you scroll the display. The names
of this node and of its Info file are omitted by Emacs from the header
line.
Besides a @samp{Next}, a node can have a @samp{Previous} or an
@samp{Up}. This node has a @samp{Previous} which is
@samp{Help-Small-Screen}, and an @samp{Up} which is @samp{Getting
Started}. Some nodes have no @samp{Previous} and some have no
@samp{Up}.
@samp{Up} links, or both. As you can see, this node has all of these
links.
@kindex n @r{(Info mode)}
Now it is time to move on to the @samp{Next} node, named @samp{Help-P}.
@format
>> Type @samp{n} to move there. Type just one character;
>> Type @kbd{n} to move there. Type just one character;
do not type the quotes and do not type a @key{RET} afterward.
@end format
@noindent
@samp{>>} in the margin means it is really time to try a command.
@format
>> If you have a mouse, and if you already practiced typing @kbd{n}
to get to the next node, click now with the right mouse button on
the @samp{Next} link to do the same ``the mouse way''.
@end format
@node Help-P, Help-^L, Help, Getting Started
@comment node-name, next, previous, up
@section Returning to the Previous node
@kindex p @r{(Info mode)}
This node is called @samp{Help-P}. The @samp{Previous} node, as you see,
is @samp{Help}, which is the one you just came from using the @kbd{n}
command. Another @kbd{n} command now would take you to the next
node, @samp{Help-^L}.
node, @samp{Help-^L}. In Emacs, @kbd{n} runs the Emacs command
@code{Info-next}, and @kbd{p} runs @code{Info-prev}.
@format
>> But do not do that yet. First, try the @kbd{p} command, which takes
you to the @samp{Previous} node. When you get there, you can do an
@kbd{n} again to return here.
>> But do not do that yet. First, try the @kbd{p} command, or click
the mouse on the @samp{Prev} link, which takes you to the
@samp{Previous} node. When you get there, you can do an @kbd{n}
again to return here.
@end format
This all probably seems insultingly simple so far, but @emph{do not} be
......@@ -279,100 +291,143 @@ do not try a new command until you are told it is time to. Otherwise,
you may make Info skip past an important warning that was coming up.
@format
>> Now do an @kbd{n} to get to the node @samp{Help-^L} and learn more.
>> Now do an @kbd{n}, or click the mouse on the @samp{Next} link, to
get to the node @samp{Help-^L} and learn more.
@end format
@node Help-^L, Help-M, Help-P, Getting Started
@comment node-name, next, previous, up
@section The Space, Delete, B and ^L commands.
@section The Space, DEL, B and ^L commands.
This node's header tells you that you are now at node @samp{Help-^L}, and
that @kbd{p} would get you back to @samp{Help-P}. The node's title is
underlined; it says what the node is about (most nodes have titles).
This node's mode line tells you that you are now at node @samp{Help-^L},
and the header line tells you that @kbd{p} would get you back to
@samp{Help-P}. The node's title is underlined; it says what the node
is about (most nodes have titles).
This is a big node and it does not all fit on your display screen.
You can tell that there is more that is not visible because you
can see the string @samp{--Top-----} rather than @samp{--All----} near
the bottom right corner of the screen.
The Space, Delete and @kbd{B} commands exist to allow you to ``move
around'' in a node that does not all fit on the screen at once.
Space moves forward, to show what was below the bottom of the screen.
Delete moves backward, to show what was above the top of the screen
(there is not anything above the top until you have typed some spaces).
@kindex SPC @r{(Info mode)}
@kindex DEL @r{(Info mode)}
@kindex BACKSPACE @r{(Info mode)}
@findex Info-scroll-up
@findex Info-scroll-down
The Space, Backspace (or DEL) and @kbd{b} commands exist to allow
you to ``move around'' in a node that does not all fit on the screen
at once. Space moves forward, to show what was below the bottom of
the screen. DEL or Backspace moves backward, to show what was above
the top of the screen (there is not anything above the top until you
have typed some spaces). In Emacs, Space runs the command
@code{Info-scroll-up}, while Backspace runs @code{Info-scroll-down}.
@format
>> Now try typing a Space (afterward, type a Delete to return here).
>> Now try typing a Space (afterward, type a Backspace to return here).
@end format
When you type the space, the two lines that were at the bottom of
the screen appear at the top, followed by more lines. Delete takes
the two lines from the top and moves them to the bottom,
@emph{usually}, but if there are not a full screen's worth of lines
above them they may not make it all the way to the bottom.
Space and Delete scroll through all the nodes in an Info file as a
single logical sequence. In this sequence, a node's subnodes appear
following their parent. If a node's menu is on the screen, Space takes
you into the subnodes listed in the menu, one by one. Once you reach
the end of a node, Space takes you to the next node or back to the
parent node.
When you type the Space, the two lines that were at the bottom of
the screen appear at the top, followed by more lines. DEL or
Backspace takes the two lines from the top and moves them to the
bottom, @emph{usually}, but if there are not a full screen's worth of
lines above them they may not make it all the way to the bottom.
If you are reading this in Emacs, note that the header line is
always visible, never scrolling off the display. That way, you can
always see the @samp{Next}, @samp{Prev}, and @samp{Up} links, and you
can conveniently go to one of these links from anywhere in the node by
clicking the mouse on one of these links.
@cindex reading Info documents top to bottom
@cindex Info documents as tutorials
Space and DEL not only move forward and backward through the current
node. When these keys hit the beginning or the end of the current
node, they move to preceding or subsequent nodes. Specifically, they
scroll through all the nodes in an Info file as a single logical
sequence. In this sequence, a node's subnodes appear following their
parent. If a node has a menu, Space takes you into the subnodes
listed in the menu, one by one. Once you reach the end of a node, and
have seen all of its subnodes, Space takes you to the next node or to
the parent's next node. This is so you could read the entire manual
top to bottom by just typing Space.
@kindex PAGEUP @r{(Info mode)}
@kindex PAGEDOWN @r{(Info mode)}
Many keyboards nowadays have two scroll keys labeled @samp{PageUp}
and @samp{PageDown} (or maybe @samp{Prior} and @samp{Next}). If your
keyboard has these keys, you can use them to move forward and backward
through the text, like with Space and Backspace. However, unlike
Space and Backspace, PageUp and PageDown keys will never scroll beyond
the beginning or the end of the current node.
@kindex C-l @r{(Info mode)}
If your screen is ever garbaged, you can tell Info to print it out
again by typing @kbd{C-l} (@kbd{Control-L}, that is---hold down ``Control'' and
type an @key{L} or @kbd{l}).
again by typing @kbd{C-l} (@kbd{Control-L}, that is---hold down
``Control'' and type an @key{L} or @kbd{l}).
@format
>> Type @kbd{C-l} now.
@end format
@kindex b @r{(Info mode)}
To move back to the beginning of the node you are on, you can type
a lot of Deletes. You can also type simply @kbd{b} for beginning.
a lot of Backspaces. You can also type simply @kbd{b} for beginning.
@format
>> Try that now. (We have put in enough verbiage to push this past
the first screenful, but screens are so big nowadays that perhaps it
isn't enough. You may need to shrink your Emacs or Info window.)
Then come back, with Spaces.
the first screenful, but screens are so big nowadays that perhaps it
isn't enough. You may need to shrink your Emacs or Info window.)
Then come back, with Spaces.
@end format
If your screen is very tall, all of this node might fit at once.
In that case, "b" won't do anything. Sorry; what can we do?
If your screen is very tall, all of this node might fit at once.
In that case, @kbd{b} won't do anything. Sorry; what can we do?
@kindex ? @r{(Info mode)}
@findex Info-summary
You have just learned a considerable number of commands. If you
want to use one but have trouble remembering which, you should type
a @key{?} which prints out a brief list of commands. When you are
finished looking at the list, make it go away by typing a @key{SPC}.
a @key{?} (in Emacs it runs the @code{Info-summary} command) which
prints out a brief list of commands. When you are finished looking at
the list, make it go away by typing a Space repeatedly.
@format
>> Type a @key{?} now. After it finishes, type a @key{SPC}.
>> Type a @key{?} now. Press @key{SPC} to see consecutive screenfuls of
the list until finished. Then type @key{SPC} several times, until
it goes away.
@end format
(If you are using the standalone Info reader, type `l' to return here.)
(If you are using the stand-alone Info reader, type @kbd{C-x 0} to
return here, that is---press and hold ``Control'', type an @kbd{x},
then release ``Control'' and @kbd{x}, and press @kbd{0}---a zero, not
the letter ``o''.)
From now on, you will encounter large nodes without warning, and
will be expected to know how to use Space and Delete to move
will be expected to know how to use Space and Backspace to move
around in them without being told. Since not all terminals have
the same size screen, it would be impossible to warn you anyway.
@format
>> Now type @kbd{n} to see the description of the @kbd{m} command.
>> Now type @kbd{n}, or click the mouse on the @samp{Next} link, to
see the description of the @kbd{m} command.
@end format
@node Help-M, Help-Adv, Help-^L, Getting Started
@comment node-name, next, previous, up
@section Menus
Menus and the @kbd{m} command
With only the @kbd{n} and @kbd{p} commands for moving between nodes, nodes
are restricted to a linear sequence. Menus allow a branching
structure. A menu is a list of other nodes you can move to. It is
actually just part of the text of the node formatted specially so that
Info can interpret it. The beginning of a menu is always identified
by a line which starts with @samp{* Menu:}. A node contains a menu if and
only if it has a line in it which starts that way. The only menu you
can use at any moment is the one in the node you are in. To use a
menu in any other node, you must move to that node first.
@section Menus and the @kbd{m} command
@cindex menus in an Info document
@cindex Info menus
With only the @kbd{n} (next) and @kbd{p} (previous) commands for
moving between nodes, nodes are restricted to a linear sequence.
Menus allow a branching structure. A menu is a list of other nodes
you can move to. It is actually just part of the text of the node
formatted specially so that Info can interpret it. The beginning of a
menu is always identified by a line which starts with @samp{* Menu:}.
A node contains a menu if and only if it has a line in it which starts
that way. The only menu you can use at any moment is the one in the
node you are in. To use a menu in any other node, you must move to
that node first.
After the start of the menu, each line that starts with a @samp{*}
identifies one subtopic. The line usually contains a brief name
......@@ -383,13 +438,13 @@ special meaning---they are only for the human reader's benefit and do
not define additional subtopics. Here is an example:
@example
* Foo: FOO's Node This tells about FOO
* Foo: Node about FOO This tells about FOO
@end example
The subtopic name is Foo, and the node describing it is @samp{FOO's Node}.
The rest of the line is just for the reader's Information.
[[ But this line is not a real menu item, simply because there is
no line above it which starts with @samp{* Menu:}.]]
The subtopic name is Foo, and the node describing it is @samp{Node
about FOO}. The rest of the line is just for the reader's
Information. [[ But this line is not a real menu item, simply because
there is no line above it which starts with @samp{* Menu:}.]]
When you use a menu to go to another node (in a way that will be
described soon), what you specify is the subtopic name, the first
......@@ -418,54 +473,57 @@ both @samp{Foo}.
@kbd{m} command is not available.
@end format
@kindex m @r{(Info mode)}
The command to go to one of the subnodes is @kbd{m}---but @emph{do
not do it yet!} Before you use @kbd{m}, you must understand the
difference between commands and arguments. So far, you have learned
several commands that do not need arguments. When you type one, Info
processes it and is instantly ready for another command. The @kbd{m}
command is different: it is incomplete without the @dfn{name of the
subtopic}. Once you have typed @kbd{m}, Info tries to read the
subtopic name.
not do it yet!} Before you use @kbd{m}, you need to learn about
commands which prompt you for more input. So far, you have learned
several commands that do not need additional input; when you typed
one, Info processed it and was instantly ready for another command.
The @kbd{m} command is different: it is incomplete without the
@dfn{name of the subtopic}. Once you have typed @kbd{m}, Info tries
to read the subtopic name.
Now look for the line containing many dashes near the bottom of the
screen. There is one more line beneath that one, but usually it is
blank. If it is empty, Info is ready for a command, such as @kbd{n}
or @kbd{b} or Space or @kbd{m}. If that line contains text ending
in a colon, it mean Info is trying to read the @dfn{argument} to a
in a colon, it means Info is trying to read more input for the last
command. At such times, commands do not work, because Info tries to
use them as the argument. You must either type the argument and
use them as the input it needs. You must either type your response and
finish the command you started, or type @kbd{Control-g} to cancel the
command. When you have done one of those things, the line becomes
blank again.
@findex Info-menu
The command to go to a subnode via a menu is @kbd{m}. After you type
the @kbd{m}, the line at the bottom of the screen says @samp{Menu item: }.
You must then type the name of the subtopic you want, and end it with
a @key{RET}.
a @key{RET}. In Emacs, @kbd{m} runs the command @code{Info-menu}.
@cindex abbreviating Info subnodes
You can abbreviate the subtopic name. If the abbreviation is not
unique, the first matching subtopic is chosen. Some menus put the
shortest possible abbreviation for each subtopic name in capital
letters, so you can see how much you need to type. It does not matter
whether you use upper case or lower case when you type the subtopic. Do
not put spaces at the end of the subtopic name; in the middle of the
subtopic name, use one space (no more!) wherever the menu item name has
a space.
unique, the first matching subtopic is chosen. Some menus put
the shortest possible abbreviation for each subtopic name in capital
letters, so you can see how much you need to type. It does not
matter whether you use upper case or lower case when you type the
subtopic. You should not put any spaces at the end, or inside of the
item name, except for one space where a space appears in the item in
the menu.
@cindex completion of Info node names
You can also use the @dfn{completion} feature to help enter the subtopic
name. If you type the Tab key after entering part of a name, it will
magically fill in more of the name---as much as follows uniquely from
what you have entered.
If you move the cursor to one of the menu subtopic lines, then you do
not need to type the argument: you just type a Return, and it stands for
the subtopic of the line you are on.
not need to type the argument: you just type a @key{RET}, and it
stands for the subtopic of the line you are on.
Here is a menu to give you a chance to practice.
Here is a menu to give you a chance to practice. This menu gives you
three ways of going to one place, Help-FOO:
@menu
This menu gives you three ways of going to one place, Help-FOO.
* Foo: Help-FOO. A node you can visit for fun.
* Bar: Help-FOO. Strange! two ways to get to the same place.
* Help-FOO:: And yet another!
......@@ -478,52 +536,105 @@ This menu gives you three ways of going to one place, Help-FOO.
Now you are ``inside'' an @kbd{m} command. Commands cannot be used
now; the next thing you will type must be the name of a subtopic.
You can change your mind about doing the @kbd{m} by typing Control-g.
You can change your mind about doing the @kbd{m} by typing
@kbd{Control-g}.
@format
>> Try that now; notice the bottom line clear.
@end format
@format
>> Then type another @kbd{m}.
@end format
>> Now type @samp{BAR} item name. Do not type Return yet.
@format
>> Now type @kbd{BAR}, the item name. Do not type @key{RET} yet.
@end format
While you are typing the item name, you can use the Delete key to
cancel one character at a time if you make a mistake.
While you are typing the item name, you can use the @key{DEL} (or
Backspace) key to cancel one character at a time if you make a
mistake.
@format
>> Type one to cancel the @samp{R}. You could type another @samp{R} to
replace it. You do not have to, since @samp{BA} is a valid abbreviation.
>> Press @key{DEL} to cancel the @samp{R}. You could type another @kbd{R}
to replace it. But you do not have to, since @samp{BA} is a valid
abbreviation.
@end format
@format
>> Now you are ready to go. Type a @key{RET}.
@end format
After visiting Help-FOO, you should return here.
After visiting @samp{Help-FOO}, you should return here.
Another way to move to the menu subtopic lines and between them is
to type @key{TAB}. Each time you type a @key{TAB}, you move to the
next subtopic line. To move to a previous subtopic line, type
@kbd{M-@key{TAB}}---that is, press and hold the Meta key and then
press @key{TAB}. (On some keyboards, the Meta key might be known as
``Alt''.)
Once you move cursor to a subtopic line, press @key{RET} to go to
that subtopic's node.
@cindex mouse support in Info mode
@kindex Mouse-2 @r{(Info mode)}
If your terminal supports a mouse, you have yet another way of going
to a subtopic. Move your mouse pointer to the subtopic line,
somewhere between the beginning @samp{*} and the colon @samp{:} which
ends the subtopic's brief name. You will see the subtopic's name
change its appearance (usually, its background color will change), and
the shape of the mouse pointer will change if your platform supports
that. After a while, if you leave the mouse on that spot, a tooltip
will pop up saying ``Mouse-2: go to that node''. (If the tooltips are
turned off or unavailable, this message is printed in the @dfn{echo
area}, the last screen line where you typed the menu subtopics in
response to the prompt.) @kbd{Mouse-2} is the second button of your
mouse---normally the rightmost button. So pressing @kbd{Mouse-2}
while the mouse pointer is on a menu subtopic goes to that subtopic.
@findex Info-mouse-follow-nearest-node
More generally, @kbd{Mouse-2} in an Info buffer runs the Emacs
command @code{Info-mouse-follow-nearest-node}, which finds the nearest
link to another node and goes there. For example, near a cross
reference it acts like @kbd{f}, in a menu it acts like @kbd{m}, on the
node's header line it acts like @kbd{n}, @kbd{p}, or @kbd{u}, etc. At
end of the node's text @kbd{Mouse-2} moves to the next node, or up if
there's no next node.
Here is another way to get to Help-FOO, a menu. You can ignore this
if you want, or else try it by typing @key{TAB} and then @key{RET}, or