1. Getting Started

This first part of this Info manual describes how to get around inside of Info. The second part of the manual describes various advanced Info commands. The third part briefly explains how to generate Info files from Texinfo files, and describes how to write an Info file by hand.

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.

There are two ways of looking at the online version of this manual:

1. Type info at your shell’s command line. This approach uses a stand-alone program designed just to read Info files.
2. Type xemacs at the command line; then type C-h i (Control-h, followed by i). This approach uses the Info mode of the XEmacs editor.

In either case, then type mInfo (just the letters), followed by <RET>—the “Return” or “Enter” key. At this point, you should be ready to follow the instructions in this manual as you read them on the screen.

1.1 Starting Info on a Small Screen

(In Info, you only see this section if your terminal has a small number of lines; most readers pass by it without seeing it.)

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 the entire text you are looking at fits on the screen, the text ‘All’ will be displayed at the bottom of the screen. In the stand-alone Info reader, it is displayed at the bottom right corner of the screen; in XEmacs, it is displayed on the modeline. If you see the text ‘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 <SPC>, the Space bar. To move back up, press the key labeled ‘Backspace’ or ‘DEL’ (on some keyboards, this key might be labeled ‘Delete’).

1.2 How to use Info

You are talking to the program Info, for reading documentation.

There are two ways to use Info: from within XEmacs or as a stand-alone reader that you can invoke from a shell using the command info.

Right now you are looking at one 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”. The mode line says that this is node ‘Help’ in the file ‘info’.

The top line of a node is its header. This node’s header (look at it now) says that the ‘Next’ node after this one is the node called ‘Help-P’. An advanced Info command lets you go to any node 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 XEmacs, the header line is displayed with a special typeface, and remains at the top of the window all the time even if you scroll through the node.

Besides a ‘Next’, a node can have a ‘Previous’ link, or an ‘Up’ link, or both. As you can see, this node has all of these links.

Now it is time to move on to the ‘Next’ node, named ‘Help-P’.

>> Type n to move there.  Type just one character;
   do not type the quotes and do not type a <RET> afterward.

‘>>’ in the margin means it is really time to try a command.

>> If you are in XEmacs and have a mouse, and if you already practiced
   typing n to get to the next node, click now with the left 
   mouse button on the ‘Next’ link to do the same “the mouse way”.

1.3 Returning to the Previous node

This node is called ‘Help-P’. The ‘Previous’ node, as you see, is ‘Help’, which is the one you just came from using the n command. Another n command now would take you to the next node, ‘Help-^L’.

>> But do not type n yet.  First, try the p command, or
   (in XEmacs) click on the ‘Prev’ link.  That takes you to
   the ‘Previous’ node.  Then use n to return here.

If you read this in XEmacs, you will see an ‘Info’ item in the menu bar, close to its right edge. Clicking the mouse on the ‘Info’ menu-bar item opens a menu of commands which include ‘Next’ and ‘Previous’ (and also some others which you didn’t yet learn about).

This all probably seems insultingly simple so far, but please don’t start skimming. Things will get complicated soon enough! Also, please do not try a new command until you are told it is time to. You could make Info skip past an important warning that was coming up.

>> Now do an n, or (in XEmacs) click the middle mouse button on
   the ‘Next’ link, to get to the node ‘Help-^L’ and learn more.

1.4 The Space, DEL, B and ^L commands

This node’s mode line tells you that you are now at node ‘Help-^L’, and the header line tells you that p would get you back to ‘Help-P’. The node’s title is highlighted and may be underlined as well; it says what the node is about.

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 text ‘Top’ rather than ‘All’ near the bottom of the screen.

The <SPC>, <BACKSPACE> (or <DEL>)(1) and b commands exist to allow you to “move around” in a node that does not all fit on the screen at once. <SPC> 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).

>> Now try typing a <SPC> (afterward, type a <BACKSPACE> to
   return here).

When you type the <SPC>, 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, 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 XEmacs, note that the header line is always visible, never scrolling off the display. That way, you can always see the ‘Next’, ‘Prev’, and ‘Up’ links, and you can conveniently go to one of these links at any time by clicking the middle mouse button on the link.

<SPC> and <DEL> not only move forward and backward through the current node. They also move between nodes. <SPC> at the end of a node moves to the next node; <DEL> (or <BACKSPACE>) at the beginning of a node moves to the previous node. In effect, these commands scroll through all the nodes in an Info file as a single logical sequence. You can read an entire manual top to bottom by just typing <SPC>, and move backward through the entire manual from bottom to top by typing <DEL> (or <BACKSPACE>).

In this sequence, a node’s subnodes appear following their parent. If a node has a menu, <SPC> 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, <SPC> takes you to the next node or to the parent’s next node.

Many keyboards nowadays have two scroll keys labeled ‘PageUp’ and ‘PageDown’ (or maybe ‘Prior’ and ‘Next’). If your keyboard has these keys, you can use them to move forward and backward through the text of one node, like <SPC> and <BACKSPACE> (or <DEL>). However, <PAGEUP> and <PAGEDOWN> keys never scroll beyond the beginning or the end of the current node.

If your screen is ever garbaged, you can tell Info to display it again by typing C-l (Control-L—that is, hold down <CTRL> and type L or l).

>> Type C-l now.

To move back to the beginning of the node you are on, you can type the <BACKSPACE> key (or <DEL>) many times. You can also type b just once. b stands for “beginning.”

>> 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 XEmacs or Info window.)
   Then come back, by typing <SPC> one or more times.

You have just learned a considerable number of commands. If you want to use one but have trouble remembering which, you should type ?, which displays a brief list of commands. When you are finished looking at the list, make it go away by typing <SPC> repeatedly.

>> Type a <?> now.  Press <SPC> to see consecutive screenfuls of
   the list until finished.  Then type <SPC> several times.  If
   you are using XEmacs, the help will then go away automatically.

(If you are using the stand-alone Info reader, type C-x 0 to return here, that is—press and hold <CTRL>, type an x, then release <CTRL> and x, and press 0; that’s 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 <SPC> 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.

>> Now type n, or click the middle mouse button on the ‘Next’ link,
   to visit the next node.

1.5 Invisible text in XEmacs Info

Before discussing menus, we need to make some remarks that are only relevant to users reading Info using XEmacs. Users of the stand-alone version can skip this node by typing ] now.

In XEmacs, certain text that appears in the stand-alone version is normally hidden, technically because it has the ‘invisibility’ property. Invisible text is really a part of the text. It becomes visible (by default) after killing and yanking, it appears in printed output, it gets saved to file just like any other text, and so on. Thus it is useful to know it is there.

You can make invisible text visible by using the command M-x visible-mode. Visible mode is a minor mode, so using the command a second time will make the text invisible again. Watch the effects of the command on the “menu” below and the top line of this node.

If you prefer to always see the invisible text, you can set Info-hide-note-references to nil. Enabling Visible mode permanently is not a real alternative, because XEmacs Info also uses (although less extensively) another text property that can change the text being displayed, the ‘display’ property. Only the invisibility property is affected by Visible mode. When, in this tutorial, we refer to the ‘XEmacs’ behavior, we mean the default XEmacs behavior.

Now type ], to learn about the ] and [ commands.

1.5.1 The ] and [ commands

If you type n now, you get an error message saying that this node has no next node. Similarly, if you type p, the error message tells you that there is no previous node. (The exact message depends on the Info reader you use.) This is because n and p carry you to the next and previous node at the same level. The present node is contained in a menu (see next) of the node you came from, and hence is considered to be at a lower level. It is the only node in the previous node’s menu (even though it was listed three times). Hence it has no next or previous node that n or p could move to.

If you systematically move through a manual by typing n, you run the risk of skipping many nodes. You do not run this risk if you systematically use <SPC>, because, when you scroll to the bottom of a node and type another <SPC>, then this carries you to the following node in the manual regardless of level. If you immediately want to go to that node, without having to scroll to the bottom of the screen first, you can type ].

Similarly, <BACKSPACE> carries you to the preceding node regardless of level, after you scrolled to the beginning of the present node. If you want to go to the preceding node immediately, you can type [.

For instance, typing this sequence will come back here in three steps: [ n [. To do the same backward, type ] p ].

Now type ] to go to the next node and learn about menus.

1.6 Menus and the m command

With only the n (next), p (previous), <SPC>, <BACKSPACE>, ] and [ 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 ‘* 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 ‘*’ identifies one subtopic. The line usually contains a brief name for the subtopic (followed by a ‘:’, normally hidden in XEmacs), the name of the node that talks about that subtopic (again, normally hidden in XEmacs), and optionally some further description of the subtopic. Lines in the menu that do not start with a ‘*’ have no special meaning—they are only for the human reader’s benefit and do not define additional subtopics. Here is an example:

* Foo:  Node about FOO.      This tells about FOO.

The subtopic name is Foo, and the node describing it is ‘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 ‘* Menu:’. Also, in a real menu item, the ‘*’ would appear at the very start of the line. This is why the “normally hidden” text in XEmacs, namely ‘: Node about FOO.’, is actually visible in this example, even when Visible mode is off.]]

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 thing in the menu line. Info uses it to find the menu line, extracts the node name from it, and goes to that node. The reason that there is both a subtopic name and a node name is that the node name must be meaningful to the computer and may therefore have to be ugly looking. The subtopic name can be chosen just to be convenient for the user to specify. Often the node name is convenient for the user to specify and so both it and the subtopic name are the same. There is an abbreviation for this:

* Foo::   This tells about FOO.

This means that the subtopic name and node name are the same; they are both ‘Foo’. (The ‘::’ is normally hidden in XEmacs.)

>> Now use <SPC> to find the menu in this node, then come back to
   the front with a b and some <SPC>s.  As you see, a menu is
   actually visible in its node.  If you cannot find a menu in a node
   by looking at it, then the node does not have a menu and the
   m command is not available.

If you keep typing <SPC> once the menu appears on the screen, it will move to another node (the first one in the menu). If that happens, type <BACKSPACE> to come back.

The command to go to one of the subnodes is m. This is very different from the commands you have used: it is a command that prompts you for more input.

The Info commands you know do not need additional input; when you type one of them, Info processes it instantly and then is ready for another command. The m command is different: it needs to know the name of the subtopic. Once you have typed m, Info tries to read the subtopic name.

Now, in the stand-alone Info, look for the line containing many dashes near the bottom of the screen. (This is the stand-alone equivalent for the mode line in XEmacs.) There is one more line beneath that one, but usually it is blank. (In XEmacs, this is the echo area.) When it is blank, Info is ready for a command, such as n or b or <SPC> or m. If that line contains text ending in a colon, it means Info is reading more input for the last command. You can’t type an Info command then, because Info is trying to read input, not commands. You must either give the input and finish the command you started, or type Control-g to cancel the command. When you have done one of those things, the input entry line becomes blank again. Then you can type Info commands again.

The command to go to a subnode via a menu is m. After you type the m, the line at the bottom of the screen says ‘Menu item: ’. You must then type the name of the subtopic you want, and end it with a <RET>.

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. 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.

You can also use the completion feature to help enter the subtopic name. If you type the <TAB> key after entering part of a name, it will fill in more of the name—as much as Info can deduce from the part 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 <RET>, and it stands for the subtopic of the line you are on. You can also click the middle mouse button directly on the subtopic line to go there.

Here is a menu to give you a chance to practice. This menu gives you three ways of going to one place, Help-FOO:

(Turn Visible mode on if you are using XEmacs.)

>>  Now type just an m and see what happens:

Now you are “inside” an 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 m by typing Control-g.

>> Try that now;  notice the bottom line clear.

>> Then type another m.

>> Now type BAR, the item name.  Do not type <RET> yet.

While you are typing the item name, you can use the <DEL> (or <BACKSPACE>) key to cancel one character at a time if you make a mistake.

>> Press <DEL> to cancel the ‘R’.  You could type another R
   to replace it.  But you do not have to, since ‘BA’ is a valid
   abbreviation.

>> Now you are ready to go.  Type a <RET>.

After visiting ‘Help-FOO’, you should return here.

Another way to move to the menu subtopic lines and between them is to type <TAB>. Each time you type a <TAB>, you move to the next subtopic line. To move to a previous subtopic line in the stand-alone reader, type M-<TAB>—that is, press and hold the <META> key and then press <TAB>. (On some keyboards, the <META> key might be labeled ‘Alt’.) In XEmacs Info, type S-<TAB> to move to a previous subtopic line (press and hold the <Shift> key and then press <TAB>).

Once you move cursor to a subtopic line, press <RET> to go to that subtopic’s node.

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 ‘*’ and the colon ‘:’ 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 small window will pop up, saying “Mouse-2: go to that node,” or the same message may appear at the bottom of the screen.

Mouse-2 is the second button of your mouse counting from the left—the middle button on a 3-button mouse. (On a 2-button mouse, you may have to press both buttons together to “press the middle button”.) The message tells you pressing Mouse-2 with the current position of the mouse pointer (on subtopic in the menu) will go to that subtopic.

More generally, Mouse-2 in an Info buffer finds the nearest link to another node and goes there. For example, near a cross reference it acts like f, in a menu it acts like m, on the node’s header line it acts like n, p, or u, etc. At end of the node’s text Mouse-2 moves to the next node, or up if there’s no next node.

>> Type n to see more commands.

1.6.1 The u command

Congratulations! This is the node ‘Help-FOO’. It has an ‘Up’ pointer ‘Help-M’, the node you just came from via the m command. This is the usual convention—the nodes you reach from a menu have ‘Up’ nodes that lead back to the menu. Menus move Down in the tree, and ‘Up’ moves Up. ‘Previous’, on the other hand, is usually used to “stay on the same level but go backwards”.

You can go back to the node ‘Help-M’ by typing the command u for “Up”. This puts you at the menu subtopic line pointing to the subnode that the u command brought you from. (Some Info readers may put you at the front of the node instead—to get back to where you were reading, you have to type some <SPC>s.)

Another way to go Up is to click Mouse-2 on the ‘Up’ pointer shown in the header line (provided that you have a mouse).

>> Now type u to move back up to ‘Help-M’.

1.7 Following Cross-References

In Info documentation, you will see many cross references. Cross references look like this: See section Cross. That text is a real, live cross reference, whose name is ‘Cross’ and which points to the node named ‘Help-Cross’. (The node name is hidden in XEmacs. Do M-x visible-mode to show or hide it.)

You can follow a cross reference by moving the cursor to it and press <RET>, just as in a menu. In XEmacs, you can also click Mouse-1 on a cross reference to follow it; you can see that the cross reference is mouse-sensitive by moving the mouse pointer to the reference and watching how the underlying text and the mouse pointer change in response.

Another way to follow a cross reference is to type f and then specify the name of the cross reference (in this case, ‘Cross’) as an argument. For this command, it does not matter where the cursor was. If the cursor is on or near a cross reference, f suggests that reference name in parentheses as the default; typing <RET> will follow that reference. However, if you type a different reference name, f will follow the other reference which has that name.

>> Type f, followed by Cross, and then <RET>.

As you enter the reference name, you can use the <DEL> (or <BACKSPACE>) key to edit your input. If you change your mind about following any reference, you can use Control-g to cancel the command. Completion is available in the f command; you can complete among all the cross reference names in the current node by typing a <TAB>.

To get a list of all the cross references in the current node, you can type ? after an f. The f continues to await a cross reference name even after displaying the list, so if you don’t actually want to follow a reference, you should type a Control-g to cancel the f.

>> Type f? to get a list of the cross references in this node.  Then
   type a Control-g and see how the ‘f’ gives up.

The <TAB>, M-<TAB> and S-<TAB> keys, which move between menu items in a menu, also move between cross references outside of menus.

Sometimes a cross reference (or a node) can lead to another file (in other words another “manual”), or, on occasion, even a file on a remote machine (although Info files distributed with XEmacs or the stand-alone Info avoid using remote links). Such a cross reference looks like this: See (texinfo)Top section ‘Overview of Texinfo’ in Texinfo: The GNU Documentation Format. (After following this link, type l to get back to this node.) Here the name ‘texinfo’ between parentheses refers to the file name. This file name appears in cross references and node names if it differs from the current file, so you can always know that you are going to be switching to another manual and which one.

However, XEmacs normally hides some other text in cross-references. If you put your mouse over the cross reference, then the information appearing in a separate box (tool tip) or in the echo area will show the full cross-reference including the file name and the node name of the cross reference. If you have a mouse, just leave it over the cross reference See (texinfo)Top section ‘Overview of Texinfo’ in Texinfo: The GNU Documentation Format, and watch what happens. If you always like to have that information visible without having to move your mouse over the cross reference, use M-x visible-mode, or set Info-hide-note-references to a value other than t (see section XEmacs Info-mode Variables).

>> Now type n to learn more commands.

1.8 Some intermediate Info commands

The introductory course is almost over; please continue a little longer to learn some intermediate-level commands.

Most Info files have an index, which is actually a large node containing little but a menu. The menu has one menu item for each topic listed in the index. (As a special feature, menus for indices may also include the line number within the node of the index entry. This allows Info readers to go to the exact line of an entry, not just the start of the containing node.)

You can get to the index from the main menu of the file with the m command and the name of the index node; then you can use the m command again in the index node to go to the node that describes the topic you want.

There is also a short-cut Info command, i, which does all of that for you. It searches the index for a given topic (a string) and goes to the node which is listed in the index for that topic. See section i searches the indices for specific subjects, for a full explanation.

If you have been moving around to different nodes and wish to retrace your steps, the l command (l for last) will do that, one node-step at a time. As you move from node to node, Info records the nodes where you have been in a special history list. The l command revisits nodes in the history list; each successive l command moves one step back through the history.

>> Try typing p p n and then three l’s, pausing in between
to see what each l does.  You should wind up right back here.

Note the difference between l and p: l moves to where you last were, whereas p always moves to the node which the header says is the ‘Previous’ node (from this node, the ‘Prev’ link leads to ‘Help-Xref’).

You can use the r command (Info-history-forward in XEmacs) to revisit nodes in the history list in the forward direction, so that r will return you to the node you came from by typing l.

The L command (Info-history in XEmacs) creates a virtual node that contains a list of all nodes you visited. You can select a previously visited node from this menu to revisit it.

The d command (Info-directory in XEmacs) gets you instantly to the Directory node. This node, which is the first one you saw when you entered Info, has a menu which leads (directly or indirectly, through other menus), to all the nodes that exist. The Directory node lists all the manuals and other Info documents that are, or could be, installed on your system.

>> Try doing a d, then do an l to return here (yes,
   do return).

The t command moves to the ‘Top’ node of the manual. This is useful if you want to browse the manual’s main menu, or select some specific top-level menu item. The XEmacs command run by t is Info-top-node.

>> Now type n to see the last node of the course.

See section Advanced Info Commands, for more advanced Info features.

1.9 Quitting Info

To get out of Info, back to what you were doing before, type q for Quit. This runs Info-exit in XEmacs.

This is the end of the basic course on using Info. You have learned how to move in an Info document, and how to follow menus and cross references. This makes you ready for reading manuals top to bottom, as new users should do when they learn a new package.

Another set of Info commands is useful when you need to find something quickly in a manual—that is, when you need to use a manual as a reference rather than as a tutorial. We urge you to learn these search commands as well. If you want to do that now, follow this cross reference to Advanced Info Commands.

Yet another set of commands are meant for experienced users; you can find them by looking in the Directory node for documentation on Info. Finding them will be a good exercise in using Info in the usual manner.

>> Type d to go to the Info directory node; then type
   mInfo and Return, to get to the node about Info and
   see what other help is available.

This document was generated by Aidan Kehoe on December 27, 2016 using texi2html 1.82.