Lynx Users Guide Version 2.3-FM
Lynx is a fully-featured World Wide Web (WWW) client for users
running cursor-addressable, character-cell display devices (e.g.,
vt100 terminals, vt100 emulators running on PCs or Macs, or any
other "curses-oriented" display). It will display hypertext
markup language (HTML) documents containing links to
files residing on the local system, as well as files residing on
remote systems running Gopher, HTTP, FTP, WAIS, and NNTP servers.
Current versions of Lynx run on UNIX and VMS. A Beta version for DOS
is also available.
Lynx can be used to access information on the World Wide Web, or
to build information systems intended primarily for local access.
For example, Lynx has been used to build several Campus Wide
Information Systems (CWIS). In addition, Lynx can be used to
build systems isolated within a single LAN.
Lynx can be started by entering the Lynx command along with
the name of a file to display. For example these commands could
all be used to display an arbitrary ASCII text file.
Select a topic
When executed, Lynx will clear the screen and display as much of
the specified file as will fit on the screen. Pressing a
down-arrow will bring up the next screen, and pressing an up-arrow
will bring up the previous screen. If no file is specified at startup,
a default file will be displayed. (The default is configured by the
system administrator when the command is installed.)
Lynx will also display files written in the HyperText
Markup Language (HTML), if the file's name ends with the
characters ".html". HTML is a file format that allows users to
create a file that contains (among other things) hypertext links
to other files. Several files linked together may be described as
a hypertext document.
For example, these commands could be used to display files
containing HTML hypertext:
When Lynx displays an HTML file, it shows links as "bold face"
text, except for one link, which is shown as "highlighted" text.
Whether "boldface" or "highlighted" text shows up as reverse
video, boldface type, or a color change, etc. depends on the
display device being used (and the way in which that device has
been configured). Lynx has no control over the exact presentation
The one link displayed as "highlighted" text is the currently
"selected" link. Lynx will display the file associated with the
selected link when a right-arrow or a Return key is pressed. To
select a particular link, press the up-arrow or down-arrow keys
until the desired link becomes "highlighted," and then press the
right-arrow or Return key to view the linked information.
Information included in the HTML file tells Lynx where to find the
linked file and what kind of server will provide it (i.e. HTTP,
When a binary file is encountered Lynx will ask the user if
he/she wishes to download the file or cancel. If the user
selects 'D' for download, Lynx will transfer the file into a
temporary location and present the user with a list of options. The
only default option is "save file to disk", which is disabled
if Lynx is running in anonymous mode. Any number of additional
download methods may be defined in the lynx.cfg file by the system
administrator. Programs like kermit, zmodem and FTP are some possible
Online help is available while viewing any document. Press the
'?' or 'H' key to see a list of help topics. See the section
titled 'Navigating hypertext documents with Lynx' for
information on navigating through the help files. ToC
To exit Lynx use the 'q' command. You will be asked whether you
really want to quit. Answering 'y' will exit and 'n' will return
you to the current document. Use 'Q' or CTRL-D to quit without verification.
If you wish to view a remote file (that is, a file residing on
some computer system other than the one upon which you are running
Lynx) without first viewing a local file, you must identify that
file by using a Uniform Resource Locator (URL). URL's take the
PROTOCOL :// HOST / PATH / FILENAME
Here are some sample URL's.
- identifies the communications
protocol used by the server that will provide the file. As
mentioned earlier, Lynx (and any WWW client) can interact with a
variety of servers, each with its own protocol.
- is the Internet address of the computer
system on which the server is running, and
- identify the directory path and file of interest.
A URL may be specified to Lynx on the command line, as in:
- HTTP (HyperText Transfer Protocol)
- FTP (File Transfer Protocol)
- WAIS (Wide Area Information Service protocol)
You may also specify a starting file for Lynx using the WWW_HOME
The process of moving within a hypertext web, selecting and displaying
links is known as "navigation." With Lynx almost all navigation can be
accomplished with the arrow keys and the numeric keypad.
setenv WWW_HOME http://info.cern.ch/default.html
define "WWW_HOME" "http://info.cern.ch/default.html"
| TOP | /|\ | Page |
arrow keys | of | | | UP |
| text 7| | 8| 9|
| SELECT | | | | |
| prev /|\| | <--- | | ---> |
| link | | | 4| 5| 6|
| BACK | SELECT | DISPLAY | | END | | | Page |
|<-- prev | next | | sel. -->| | of | | | DOWN |
| doc. | link \|/| link | | text 1| \|/ 2| 3|
There are also a few other keyboard commands to aid in navigation.
Some of these commands depend on the fact that Lynx keeps a list of
each file you visit called the "history list". The "backspace" or
"delete" key will show you the whole history list. Any of the
documents shown in the list may be revisited by selecting them from
the history screen. The 'm' key command will take you back to the
starting document unless you specified the
option at the command line.
The 'i' key presents an index of documents. The default index is usually
a document pointing to servers around the world, but the index can be
changed by the system administrator or on the command line using the
-index switch, and therefore depends on how the Lynx
program you are using was configured.
If you choose a link to a server with active access
authorization Lynx will automatically prompt for a
username and a password. If you give the correct information, you will
then be served the requested information. Lynx will automatically send
your username and password to the same server if it is needed
Documents may be printed using the 'p' command. After pressing
the 'p' key a menu of Print Options will be displayed. The menu
will vary according to several factors. First, some sites set up
special accounts to let users run Lynx to access local information
systems. Typically these accounts require no passwords and do not
require users to identify themselves. As a result such accounts
are called "anonymous" accounts, and their users are considered
"anonymous" users. In most configurations, all Lynx users
(including anonymous users) are able to mail files to themselves
and print the entire file to the screen.
Additional print options are available for users who are using
Lynx from their own accounts (that is, so-called "non-anonymous
users"). In particular, the
Two commands activate searching in Lynx: "/" and "s". While
viewing a normal document use the "/" command to find a word or
phrase within the current document. The search type will depend
on the search option setting in the options menu (see below). The
search options are case sensitive and case insensitive. Some
documents are designated "index documents". These documents can
be searched to retrieve additional information from an index
server. The "s" key allows searching of index documents. ToC
The Lynx Options Menu may be accessed by pressing the 'o' key.
The current Lynx Options Menu contains the following configurable
"Save to a local file"
option allows you to save the document into a file on your disk
space. Any number of additional print options may also be
available as configured by your system administrator. ToC
E)ditor : emacs
D)ISPLAY variable : aixtest.cc.ukans.edu:0.0
B)ookmark file : home_page
F)TP sort criteria : By Filename
P)ersonal mail address : email@example.com
S)earching type : CASE INSENSITIVE
C)haracter set : ISO Latin 1
V)I keys : OFF
e(M)acs keys : OFF
K)eypad as arrows
or Numbered links : Numbers act as arrows
l(I)st directory style : Mixed style
U)ser mode : Advanced
L)ocal execution links : Always off
An option can be changed by entering the capital letter of the option
you want to change (i.e. 'E' for Editor). For fields where text must
be entered, simply enter the text by typing on the keyboard. The
Backspace and Delete keys can be used to correct mistakes, and CTRL-U
can be used to erase the whole line.
When you are done entering a change press the Return key to get
back to the
For fields where you must choose from a list of choices, press any key
to toggle the choices and press the Return key to finish the change.
When you are done changing options use the 'r' command to return
to Lynx or the '>' command to save the options to a
.lynxrc file and return to Lynx.
The following table describes the options available on the Options
At any time while viewing documents within Lynx, you may use the 'c'
command to send a mail message to the owner of the current document if
the author of the document has specified ownership. If no ownership
is specified then comments are disabled. Certain links called
"mailto:" links will also allow you to send mail to other people.
Using the mail features within Lynx is straightforward.
- The editor to be invoked when editing browsable files, and
sending mail or comments. The full pathname of the editor command
should be specified when possible.
- DISPLAY variable
- This option is only available on UNIX systems and is only relevant
to X Window users. The DISPLAY variable is picked up automatically
from the environment if it has been previously set.
- Bookmark file
- This is the filename and location of your personal bookmark file.
The bookmark file allows frequently travelled links to be stored in
a personal easy to access file. Using the 'a' command (see below)
you may save any link into your bookmark file. If the path specified
does not begin with a slash then the path will reference your home
- FTP sort criteria
- This option allows you to specify how files will be sorted within
FTP listings. The current options include
By Filename", "
By Type", and "
- Personal mail address
- This mail address will be used to help you send files to yourself
and will be included as the From: address in any mail or comments
that you send. It will also be sent as the From: field in all
HTTP get requests.
- Searching type
- Searching type has two possible values: CASE INSENSITIVE
(default) and CASE SENSITIVE. The searching type effects
inter-document searches only, and determines whether searches for
words within documents will be done in a case-sensitive or
- VI keys
- If set to ON then the lowercase h,j,k, and l
keys will be mapped to left, down, up, and right arrow, respectively.
- Emacs keys
- If set to ON then the CTRL-P, CTRL-N, CTRL-F, and CTRL-B
keys will be mapped to up, down, right, and left arro arrow arroww, respectively.
- Keypad as arrows or numbered links
- This option gives the choice between navigating with the arrow keys
or having every link numbered so that the
links may be selected by numbers as well as using
the arrow keys.
- List directory style
- Applies to Directory Editing. Files and directories can be
presented in the following ways:
- Mixed style
- Files and directories are listed together in alphabetical
- Directories first
- Files and directories are separated into two alphabetical
lists. Directories are listed first.
- Files first
- Files and directories are separated into two alphabetical
lists. Files are listed first.
- User Mode
- There are three possible choices: Novice, Intermediate, and Advanced.
- In Novice mode two lines of help are displayed at the
bottom of the screen.
- Intermediate mode turns off the help lines.
- Advanced mode displays the URL of the currently selected
link at the bottom of the screen.
- Local execution scripts or links
- Local execution can be activated by the system administrator.
If it has not been activated you will not see this option
in the options menu.
When a local execution script is encountered Lynx
checks the users options to see whether the script can be
executed. Users have the following options:
- Always off
- Local execution scripts will never be executed
- For Local files only
- Local execution scripts will only be executed if the
script to be executed resides on the local machine, and
is referenced by a URL that begins with "file://localhost"
- Always on
- All local exection scripts will be executed
- If the users options permit the script to be executed Lynx will
spawn a shell and run the script. If the script cannot be
executed Lynx will show the script within the Lynx window and
inform the user that the script is not allowed to be executed
and will ask the user to check his/her options. ToC
Once you have decided to send a comment or have selected a
"mailto:" link a new screen will appear showing you who you are
sending the message to. Lynx will ask for your name, your e-mail
address, and the subject of the message. If you have filled in the
"personal mail address" field in the Options Menu, your e-mail address
will be filled in automatically. After entering the above information,
if you have an editor defined in the Options Menu and you are not an
anonymous user then your specified editor will be spawned for you so
that you can enter your message. If you do not have an editor
defined or you are an anonymous user, a simple line mode input
scheme will allow you to enter your message.
To finish sending the message, exit your spawned editor or, if you are
using the simple line mode input scheme, type a "." (period) on a line
by itself. You will be asked a final time whether to send the
message. If you press 'y' then the message will be sent, if you press
'n' the message will be deleted. ToC
While reading news articles with Lynx you should
see a link that says "Reply to user@host" and a link that says
"Reply to newsgroup(s)"
This section describes the Lynx Forms Interface. HTML gives document
providers the ability to create on-line forms which may be filled out
when the document is viewed. When a form is submitted the information
on the form can be used to search a database or complete a survey.
- Reply to user@host
- user@host will actually appear as the mail address of the
person who posted the news article. Selecting the link will
allow you to send a message to the person who wrote the message
you are currently viewing. You will be given the option of
including the original message in your reply.
- Reply to newsgroup(s)
- Selecting this link will allow you to post back to the
newsgroup that you are currently reading and any newsgroups
that the message may be cross-posted to. You will be given
the option of including the original message in your reply.
Once you have typed in your message the inews program
will be called to post your message to your news host.
An HTML Form provides for the use of buttons or to perform an action
(such as submit), checkboxes and radio buttons to select
options from a list, and fields for entering text.
You can move around the form using the standard Lynx navigation keys.
UP ARROW and DOWN ARROW keys respectively select the
previous or next field, box, or button. The TAB key selects the
next field, box, or button.
- Buttons are displayed in the same way that Lynx displays links in
a document. To "push" the button press the RIGHT ARROW or
- Checkboxes and Radio buttons
- Checkboxes and radio buttons are displayed as parenthesis:
(). When a box is checked or a button selected, an asterisk
appears within the parenthesis: (*). To check a box or select
a radio button press the RIGHT ARROW or RETURN key.
- Selection Fields
- Selection fields are displayed as brackets with the default option
displayed between them: [default__]. To select an option press
theRIGHT ARROW or RETURN key. A box with a border of
asterisks will appear with the list of possible options listed within
the box. Use the UP ARROW and DOWN ARROW keys to move
the cursor between options and the RIGHT ARROW or RETURN
key to select an option.
- Text Entry Fields
- Text entry fields are displayed as a row of underscores the length
of the entry field: _______. You may enter text directly by
typing at the keyboard. Use the BACKSPACE key to correct
errors. If you input more text than the field can hold your input will be
truncated. If you fill a text field the cursor will not move off
the field but remain at the last field position.
NOTE:If you have a text input field selected you will not have
access to any of the Lynx keystroke commands. Select a button or box
when you want to use Lynx keystrokes.
When viewing HTML documents it is possible to view the unrendered
(i.e., the original HTML) source of the document by pressing the '\'
(backslash) key. The document will be reloaded from the server or
disk and displayed on the screen unrendered. When viewing unrendered
documents you may print them as any normal document.
Selecting the Print to a local file option from the Print Menu,
makes it possible to save the source of the document to disk so that
you may have a local copy of the document.
NOTE: When saving an HTML document it is important to name the
document with a ".html" extension, if you want to read it with Lynx
Lynx can allow users to edit documents that reside on the local
system. To enable editing, documents must be referenced using a
"file:" URL or by specifying a plain filename on the command line as
in the following two examples:
In addition, the user must also specify an editor in the Options Menu
so that Lynx knows which editor to use. If the file is specified
correctly and an editor is defined, then you may edit documents by
using the 'e' command. When the 'e' command is entered your specified
editor is spawned to edit the file. After changes are completed, exit
your editor and you will return to Lynx. Lynx will reload and render
the file so that changes can be immediately examined. ToC
The CTRL-R command will reload and rerender the file that you are
currently viewing. CTRL-L or CTRL-W will refresh or wipe the screen to remove
or correct any errors that may be caused by operating system or other
It is often useful to place a bookmark to aid in returning quickly to
a document. To use the bookmark feature you must first use the Options
Menu to specify a bookmark filename.
To save a bookmark to the document you wish to place in the
bookmark file press the 'a' key and you will be asked
Answer 'd' to save a link to the document you are currently
viewing or 'l' to save the link that is currently selected on the
page. Selecting 'c' will cancel without saveing anything to your
Save D)ocument or L)ink to bookmark
file or C)ancel? (d,l,c):
Use the 'v' command to view the list of bookmarks you have saved.
While viewing the bookmark list you may select a bookmark as you would
any other link. ToC
A feature similar to the Lynx bookmarks is the jump command. The jump
command allows you to enter a shortcut name to access a URL. If the jump
feature is active, typing 'j' will produce a prompt where you may enter
the shortcut name. Type '?' at the jump prompt for a list of shortcut
Note to System Administrators: Read the "lynx.cfg" file on how to set up
the jump command for your system and how to define shortcut names.
A new feature in lynx is DIRED support. When a local directory is accessed
using a URL of the form
file://localhost/path/, a new set of
commands is available. With DIRED support you can create, edit,
delete, copy, and move files on your local system. The commands
available in DIRED mode are
- Type 'c' to create a new file. New file will be empty.
- Type 'd' to download selection using one of the options defined
by your system administrator.
- Type 'e' to spawn the editor defined in options menu and load selected
file for editing.
- Type 'f' to show full menu of options available for selection.
Menu may vary according to type of file selected and compression
- Type 'm' to modify the name or location of file. Then type 'n' to rename
the file or 'l' to move the file to a different location.
- Type 'r' to remove the selected file or directory.
- Type 't' to tag highlighted file. Further operations will be performed
on tagged files instead of highlighted ones.
- Type 'u' to upload a file to the present directory. Upload methods are
defined by your system administrator.
The basic syntax of the Lynx command can be represented as one of
- When '!' is pressed your default shell will be
spawned. When you quit or exit the shell you will return to Lynx.
(Usually 'exit' under UNIX and 'logout' under VMS) This command is
usually disabled for anonymous users.
- The 'g' command allows any URL to be viewed. Pressing
the 'g' command will bring up a prompt asking for a URL.
Type in the URL that you wish to view.
- The '=' command shows information about the current document
and the currently selected link if there is one. The number of
lines in the file, URL, title, owner, and type are shown.
- Lynx supports completely interruptable I/O processes. Press the 'z'
key at any time during a connect or transfer process and the process
will be halted. If any data was transferred before the interrupt,
it will be displayed. ToC
lynx [options] startup_file
No options are required, nor is a starting file required.
White space may be substituted for any equal sign (=) appearing
in the option list above. ToC
Lynx grew out of efforts to build a campus-wide information system
at The University of Kansas. The earliest versions of Lynx
provided a user-friendly, distributed hypertext interface for
users connected to multiuser (UN*X and VMS) systems via
curses-oriented display devices. A custom hypertext format was
developed to support hypertext links to local files and files on
remote Gopher servers. Using Gopher servers for distributed file
service allowed information providers to publish information from
a wide variety of platforms (including UN*X, VMS, VM/CMS and
Macintosh). In addition, Lynx became the most user-friendly
Gopher client, although that was only an ancillary capability.
- is the file that Lynx will load at start-up.
- If no file is specified, Lynx will use a default
starting file and base directory determined during installation.
- If a specified file is local (i.e., not a URL) Lynx
displays that file and uses the directory in which that file
resides as the base directory.
- If a URL is specified, the file will be retrieved,
and only the server base directory will be relevant
to further accesses.
- can be selected from the following list, where items in all-caps
indicate that a substitution must be made.
- used to specify the anonymous account.
- id and password for protected pages.
- enable case-sensitive string searching.
- set the
NUMBER of documents cached in memory.
The default is 10.
- specifies a Lynx configuration file other than the default
- set the display variable for X rexeced programs.
- dumps the formatted output of the default document or one
specified on the command line to standard out.
Under UNIX this can be used in the following way:
lynx -dump http://info.cern.ch/default.html.
- enable edit mode using the specified
EDITOR. (vi, ed, emacs, etc.)
- enable emacs-like key movement.
- the status code from the HTTP request is placed in this file
- forces the first document to be interpreted as HTML.
- disable ftp access.
- properly formatted data for a get form are read in from
stdin and passed to the form. Input is terminated by a
line that starts with '---'.
- print this Lynx command syntax usage message.
- set the default index file to the specified
- mime header is returned as well.
- disable print functions.
- don't follow URL redirections
- disable the retrieval status messages.
- properly formatted data for a post form are read in from
stdin and passed to the form. Input is terminated by a
line that starts with '---'.
- enable print functions. (default)
- allows a list of services to be disabled
selectively and takes the following form:
This list is printed if no options are specified.
- restricts all options.
- disallow changing the location of the bookmark
- same as command line option -anonymous.
Disables default services for anonymous users.
Currently set to all restricted except for:
inside_telnet, outside_telnet, inside_news,
inside_ftp, outside_ftp, inside_rlogin,
outside_rlogin, jump, mail and goto. Defaults
are setable within userdefs.h.
- disallow saving binary files to disk in the
- disallow downloaders in the download menu.
- disallow editing.
- disable execution scripts.
- disallow the user from changing the local
- disallow using G)oto to go to file: URL's.
- disable the 'g' (goto) command.
- disallow ftps for people coming from inside your
- disallow USENET news posting for people coming
from inside you domain.
- disallow rlogins for people coming from inside
- disallow telnets for people coming from inside
- disable the 'j' (jump) command.
- disable mailing feature.
- disable USENET News posting.
- disallow saving options in .lynxrc.
- disallow ftps for people coming from outside your
- disallow USENET news posting for people coming
from outside you domain.
- disallow rlogins for people coming from outside
- disallow telnets for people coming from
outside your domain.
- disallow most print options.
- disallow shell escapes.
- disable recognition of rlogin commands.
- If enabled the cursor will not be hidden in the right hand
corner but will instead be positioned at the start of the
currently selected link. show cursor is the default for systems
without FANCY_CURSES capabilities, and the default
configuration can be changed in userdefs.h.
- works the same as dump but outputs HTML source instead of
- disable recognition of telnet commands.
- tell Lynx what terminal type to assume its talking to.
(This may be useful for remote execution, when, for example,
Lynx connects to a remote TCP/IP port that starts a script that,
in turn, starts another Lynx process.)
- turns on WWW trace mode.
- enable vi-like key movement.
- print version information
This distributed approach let providers retain complete control
over their information, but it made communication between users
and providers somewhat more difficult. Following the lead of Neal
Erdwien, of Kansas State University, the Lynx hypertext format was
extended to include links for including ownership information with
each file. This information made it possible for users running
Lynx clients to send comments and suggestions via e-mail to the
This early version of Lynx was also augmented to support hypertext
links to programs running on remote systems. It included the
ability to open a Telnet connection, as well as the ability to
start programs via rexec, inetd, or by direct socket connects.
These capabilities were included to allow users to access
databases or custom program interfaces.
A subsequent version of Lynx incorporated the World Wide Web
libraries to allow access to the full list of WWW servers, along
with the option to build hypertext documents in HTML, rather than
the native Lynx format. HTML has become far more widely used, and
the native format has been phased out. With the addition of the
WWW libraries, Lynx became a fully-featured WWW client, limited
only by the display capabilites offered in the curses
At The University of Kansas, Lynx is used in several different
ways to give users access to the campus wide information system.
First, it is run on several local clients from a script named
"kufacts" that points to the starting file located on a local
server. Second, it runs whenever a user logs into an account
called "kufacts" on a system named kufacts.cc.ukans.edu. Users
without a local account may use this system to explore the KU CWIS
and experiment with Lynx.
Lynx was designed by Lou Montulli, Charles Rezac and Michael Grobe
of Academic Computing Services at The University of Kansas. Lynx
was implemented by Lou Montulli and maintained by Garrett Arch
Blythe. Now Jeff Porter, Craig Lavender and Ravikumar Kolli
maintain Lynx. Special thanks goes to Foteos Macrides for his
enthusiasm that has kept Lynx development going during the disruptive
staff changes at the University of Kansas.
Lynx has incorporated code from a variety of sources along the
way. The earliest versions of Lynx included code from Earl Fogel
of Computing Services at the University of Saskatchewan, who
implemented HYPERREZ in the UN*X environment. Those versions also
incorporated libraries from the UN*X Gopher clients developed at
the University of Minnesota, and the later versions of Lynx rely
on the WWW client library code developed by Tim Berners-Lee (and
others) and the WWW community.
Lynx is presently available via anonymous FTP from
Doslynx is also available from
For a tutorial introduction to HTML see:
For a quick reference guide to HTML see:
For reference information on HTML see:
Academic Computing Services
The University of Kansas
Lawrence, Kansas 66045