Lynx Users Guide v2.7

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 character-cell display). It will display Hypertext Markup Language (HTML) documents containing links to files on the local system, as well as files on remote systems running http, gopher, ftp, wais, nntp, finger, or cso/ph/qi servers, and services accessible via logins to telnet, tn3270 or rlogin accounts (see URL Schemes Supported by Lynx). Current versions of Lynx run on Unix and VMS.

Lynx can be used to access information on the WWW, 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.

Table of Contents

Lynx online help

Online help is available while viewing any document. Press the '?' or 'H' key (or the 'h key if vi-like key movement is not on) to see a list of help topics. See the section titled Navigating hypertext documents with Lynx for information on navigating through the help files.

In addition, a summary description of all the Lynx keystroke commands and their key bindings is available by pressing the 'K' key (or the 'k' key if vi-like key movement is not on). [ToC]

Viewing local files with Lynx

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 or HTML file:
UNIX
lynx filename
lynx /home/my-dir/filename
lynx ~/filename
VMS
lynx filename
lynx dua5:[my-directory]filename
lynx /dua5/my-directory/filename
lynx ~/filename
lynx sys$login:filename
lynx /sys$login/filename

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 display local files written in the HyperText Markup Language (HTML), if the file's name ends with the characters .html, .htm, .shtml, .htmlx, .html3, or .ht3. 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. If the filename does not have one of the suffixes mapped by Lynx to HTML, the -force_html command line option can be included to force treatment of the file as 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 of links.

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, Gopher, etc.).

Lynx renders HTML files and saves the rendition, not the source, for initial display and should you select the link again. If you do select a link again and have reason to desire a new fetch and rendering of the file, use the NOCACHE command, normally mapped to 'x' and 'X', instead of the right-arrow or Return key when positioned on the link. You also can force a new fetch and rendering of the currently displayed document via the RELOAD command, normally mapped to Control-R.

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 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 options. [ToC]

Leaving Lynx

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 Control-D to quit without verification. [ToC]

Starting Lynx with a Remote File

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). URLs take the general form:

PROTOCOL :// HOST / PATH

where

PROTOCOL
identifies the communications protocol (scheme) 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.
HOST
is the Internet address of the computer system on which the server is running, and
PATH
is a scheme-specific field which for some schemes may correspond to a directory path and/or filename.
Here are some sample URLs.
HTTP (HyperText Transfer Protocol)
http://www.crl.com/~subir/lynx.html
Gopher
gopher://gopher.micro.umn.edu/11/
FTP (File Transfer Protocol)
ftp://ftp2.cc.ukans.edu/pub/lynx/README
WAIS (Wide Area Information Service protocol)
wais://cnidr.org/directory-of-servers
A URL may be specified to Lynx on the command line, as in:
lynx http://kufacts.cc.ukans.edu/cwis/kufacts_start.html
Lynx also will attempt to create a complete URL if you include adequate portions of it in the startfile argument. For example:
wfbr will be expanded to:
http://www.wfbr.edu/ and:
ftp.more.net/pub will be expanded to:
ftp://ftp.more.net/pub
See URL Schemes Supported by Lynx for more detailed information. [ToC]

Starting Lynx with the WWW_HOME environment variable.

You may also specify a starting file for Lynx using the WWW_HOME environment variable,
UNIX
ksh
export WWW_HOME=http://www.w3.org/
csh
setenv WWW_HOME http://www.w3.org/
VMS
define "WWW_HOME" "http://www.w3.org/"
Note that on VMS the double-quoting must be included to preserve casing.

Navigating hypertext documents with Lynx

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.
                                       +-------+-------+-------+
                                       | 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. The Control and Function keys used for navigation within the current document are described in Scrolling and Other useful commands. Some additional commands depend on the fact that Lynx keeps a list of each link you visited to reach the current document, called the History Page, and a list of all links visited during the current Lynx session, called the Visited Links Page. The HISTORY keystroke command, normally mapped to Backspace or Delete, will show you the History Page of links leading to your access of the current document. Any of the previous documents shown in the list may be revisited by selecting them from the history screen. The VLINKS keystroke command, normally mapped to uppercase 'V', will show the Visited Links Page, and you similarly can select links in that list. The MAIN_MENU keystroke command, normally mapped to 'm' and 'M', will take you back to the starting document unless you specified the -homepage=URL option at the command line. Also, the LIST keystroke command, normally mapped to 'l' and L', will create a compact list of all the links in the current document, and they can be selected via that list.

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=URL 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 again. [ToC]

Printing, Mailing, and Saving rendered files to disk.

Rendered HTML documents, and plain text files, may be printed using the 'p' command while viewing the document. 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 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.

Some options, such as Save to a local file, involve prompting for an output filename. All output filename entries are saved in a circular buffer, and any previous entries can be retrieved for re-use by pressing the up-arrow or down-arrow keys at the prompt.

Note that if you want exact copies of text files without any expansions of TAB characters to spaces you should use the Download options. [ToC]

Viewing the HTML document source and editing documents

When viewing HTML documents it is possible to retrieve and display the unrendered (i.e., the original HTML) source of the document by pressing the '\' (backslash) key. The document must be reloaded from the server or disk to be displayed on the screen unrendered, since Lynx originally rendered what it received and does not still have it as source. 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 source, but it is better to Download the source.

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 again later.

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:

Command
lynx file://localhost/FULL/PATH/FILENAME
lynx path/filename.html
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]

Downloading and Saving source files.

If the DOWNLOAD keystroke command ('d' or D) is used when positioned on a link for an HTML, plain text, or binary file, Lynx will transfer the file, without rendering or modification, into a temporary location and present the user with a list of options, as when a link for a binary file of a type for which no viewer has been mapped is activated. As described above, the only default Download option is Save to disk, which is disabled if Lynx is running in anonymous mode, and any number of additional download methods such as kermit and zmodem may be defined in the lynx.cfg file by the system administrator. Downloading the sources of HTML and plain text files, instead of toggling to display the source ('\') and then using Printing options, ensures that no modifications of the source (e.g., expansions of TAB characters to a series of spaces) will occur.

Some options, such as Save to disk, involve prompting for an output filename. All output filename entries are saved in a circular buffer, and any previous entries can be retrieved for re-use by pressing the up-arrow or down-arrow keys at the prompt. [ToC]

Reloading files and refreshing the display

The RELOAD (Control-R) command will reload and re-render the file that you are currently viewing. The REFRESH (Control-L or Control-W) command will refresh or wipe the screen to remove or correct any errors that may be caused by operating system or other messages.

The NOCACHE ('x' or 'X') command can be used in lieu of ACTIVATE (Return or right-arrow) to request an uncached copy and new rendition for the current link, or resubmission of a FORM, if a cache from a previous request or submission exits. The request or submission will include Pragma: no-cache and Cache-Control: no-cache in its headers. Note that FORMs with POST content will be resubmitted regardless of whether the NOCACHE or ACTIVATE command is used (see Lynx and HTML Forms). [ToC]

Lynx searching commands

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. The search options are case sensitive and case insensitive. These searches are entirely local to Lynx.

Some documents are designated index documents by virtue of an ISINDEX element in their HEAD section. These documents can be used to retrieve additional information based on searches using words or phrases submitted to an index server. The Lynx statusline will indicate that you are viewing such a document, and if so, the 's' key will invoke a statusline prompt to enter a query string. The prompt can be specified via a PROMPT attribute in the ISINDEX element. Otherwise, Lynx will use an internally configured prompt. The address for submitting the search can be specified via an HREF or ACTION attribute. Otherwise, Lynx will use the current document's URL and append your query string as a ?searchpart (see Supported URLs).

All search words or strings which you have entered during a Lynx session are saved in a circular buffer, and can be retrieved for re-use by pressing the up-arrow or down-arrow keys at the prompt for a search word or string. Also, you can use the 'n'ext command to repeat a search with the last-entered search word or phrase, starting from the current position in the document. The word or phrase matches will be highlighted throughout the document, but such highlighting will not persist for new documents, or if the current document is reloaded. The search cycles to the top of the document if the word or phrase is not located below your current position.

Although HTML Forms have largely replaced index documents for searches via http servers, they are still useful for performing searches directly via WAIS or Gopher servers in conjunction with the internal gateways for such servers. For example, an HTML index document can act as a cover page describing a WAIS database and how to formulate query strings for searching it, and include an element such as:
<ISINDEX PROMPT="Enter WAIS query:"
HREF="wais://net.bio.net/biologists-addresses">

for submitting a search of the Biologist's Addresses database directly to the net.bio.net WAIS server. [ToC]

Lynx Options Menu

The Lynx Options Menu may be accessed by pressing the 'o' key. The current Options Menu contains the following configurable options.
                      Options Menu

     E)ditor                      : emacs
     D)ISPLAY variable            : aixtest.cc.ukans.edu:0.0
     mu(L)ti-bookmarks: OFF       B)ookmark file: lynx_bookmarks.html
     F)TP sort criteria           : By Filename
     P)ersonal mail address       : montulli@ukanaix.cc.ukans.edu
     S)earching type              : CASE INSENSITIVE
     display (C)haracter set      : ISO Latin 1
     raw 8-bit or CJK m(O)de      : ON
     preferred document lan(G)uage: en
     preferred document c(H)arset : NONE
     V)I keys: OFF    e(M)acs keys: OFF     sho(W) dot files: OFF
     popups for selec(T) fields   : ON
     K)eypad mode                 : Numbers act as arrows
     li(N)e edit style            : Default Binding
     l(I)st directory style	  : Mixed style
     U)ser mode                   : Advanced
     user (A)gent                 : [User-Agent header]
     local e(X)ecution links	  : FOR LOCAL FILES ONLY
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 Line Editor can be used to correct mistakes, and Control-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 Command? prompt.

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 Menu:

Editor
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 relevant to X Window users. The DISPLAY (Unix) or DECW$DISPLAY (VMS) variable is picked up automatically from the environment if it has been previously set.
Multi-bookmarks
Lynx supports a default bookmark file, and up to 26 total bookmark files (see below). When multi-bookmarks is OFF, the default bookmark file is used for the 'v'iew bookmarks and 'a'dd bookmark link commands. If multi-bookmark support is available in your account, the setting can be changed to STANDARD or ADVANCED. In STANDARD mode, a menu of available bookmarks always is invoked when you seek to view a bookmark file or add a link, and you select the bookmark file by its letter token (see Bookmark file, below) in that menu. In ADVANCED mode, you instead are prompted for the letter of the desired bookmark file, but can enter '=' to invoke the STANDARD selection menu, or RETURN for the default bookmark file.
Bookmark file
When multi-bookmarks is OFF, this is the filename and location of your default personal bookmark file. Enter 'B' to modify the filename and/or location via the Line Editor. Bookmark files allow frequently traveled links to be stored in personal easy to access files. Using the 'a'dd bookmark link command (see Lynx bookmarks) you may save any link that does not have associated POST content into a bookmark file. All bookmark files must be in or under your account's home directory. If the location specified does not begin with a dot-slash (./), its presence will still be assumed, and referenced to the home directory. When multi-bookmarks is STANDARD or ADVANCED, entering 'B' will invoke a menu of up to 26 bookmark files (associated with the letters of the English alphabet), for editing their filenames and locations (filepath), and descriptions. Lynx will create bookmark files, if they don't already exist, when you first 'a'dd a bookmark link to them. However, if you've specified a subdirectory (e.g., ./BM/lynx_bookmarks.html), that subdirectory must already exist. Note that on VMS you should use the URL syntax for the filepath (e.g., not [.BM]lynx_bookmarks.html).
FTP sort criteria
This option allows you to specify how files will be sorted within FTP listings. The current options include "By Filename", "By Size", "By Type", and "By Date".
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 if inclusion of that HTTP header has not been disabled via the NO_FROM_HEADER definition in lynx.cfg or via the -nofrom command line option.
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 case-insensitive manner.
Display Character set
This option allows you to set up the default character set for your specific terminal. The character set provides a mapping of 8-bit ISO Latin character entities and/or Asian (CJK) characters into viewable characters and should be set in relation to your terminal's character set if you will be viewing such characters with Lynx. You must have the selected character set installed on your terminal.
Raw 8-bit or CJK Mode
Whether 8-bit characters are are assumed to correspond with the selected character set and therefore are processed without translation via the ISO Latin 1 conversion tables. Should be ON by default when the selected character set is ISO Latin 1, or is one of the Asian (CJK) sets and the 8-bit characters are Kanji multibytes. Should be OFF for the other character sets, but can be turned ON when there's a match, e.g., the document's charset is ISO-8859-2 and ISO Latin 2 has been selected. Should be OFF when an Asian (CJK) set is selected but the document is ISO-8850-1. The setting also can be toggled via the RAW_TOGGLE command, normally mapped to '@', and at startup via the -raw switch.
Preferred Document Language
The language you prefer if multi-language files are available from servers. Use MIME abbreviations, e.g., en for English, fr for French, etc. Can be a comma-separated list in descending order of preferences.
Preferred Document Charset
The character set you prefer if sets in addition to ISO-8859-1 and US-ASCII are available from servers. Use MIME notation (e.g., ISO-8859-2) and do not include ISO-8859-1 or US-ASCII, since those values are always assumed by default. Can be a comma-separated list in descending order of preferences.
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. The uppercase H, J, K, and L keys remain mapped to their configured bindings (normally HELP, JUMP, KEYMAP, and LIST, respectively).
Emacs keys
If set to ON then the CTRL-P, CTRL-N, CTRL-F, and CTRL-B keys will be mapped to up-arrow, down-arrow, right-arrow, and left-arrow, respectively. Otherwise, they remain mapped to their configured bindings (normally UP_TWO lines, DOWN_TWO lines, NEXT_PAGE, and PREV_PAGE, respectively).
Show dot files
If display/creation of hidden (dot) files/directories is enabled, you can turn the feature on or off via this setting.
Popups for select fields
Lynx normally uses a popup window for the OPTIONs in form SELECT fields when the field does not have the MULTIPLE attribute specified, and thus only one OPTION can be selected. The use of popup windows can be disabled by changing this setting to OFF, in which case the OPTIONs will be rendered as a list of radio buttons. Note that if the SELECT field does have the MULTIPLE attribute specified, the OPTIONs always are rendered as a list of checkboxes.
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.
Line edit style
This option allows you to set alternate key bindings for the built-in line editor, if your system administrator has installed alternates. Otherwise, Lynx uses the Default Binding.
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 order.
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.
Novice
In Novice mode two lines of help are displayed at the bottom of the screen.
Intermediate
Intermediate mode turns off the help lines.
Advanced
Advanced mode displays the URL of the currently selected link at the bottom of the screen.
User Agent
The header string which Lynx sends to servers to indicate the User-Agent is displayed here. Changes may be disallowed via the -restrictions switch. Otherwise, the header can be changed temporarily to a string such as L_y_n_x/2.7 for access to sites which discriminate against Lynx based on checks for the presence of "Lynx" in the header. If changed during a Lynx session, the default User-Agent header can be restored by deleting the modified string in the Options Menu. Whenever the User-Agent header is changed, the current document is reloaded, with the no-cache flags set, on exit from the Options Menu. Changes of the header are not saved in the RC file.
NOTE that Netscape Communications Corp. has claimed that false transmissions of "Mozilla" as the User-Agent are a copyright infringement, which will be prosecuted. DO NOT misrepresent Lynx as Mozilla. The Options Menu issues a warning about possible copyright infringement whenever the header is changed to one which does not include "Lynx" or "lynx".
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 execution 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]

Comments and mailto: links

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.

Once you have decided to send a comment or have selected a mailto: link a new screen will appear showing you to whom you are sending the message. 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', you will be prompted whether to append your signature file if one was defined in lynx.cfg and is accessible, and then the message will be sent, whereas if you press 'n' the message will be deleted. Entering Control-G in response to any prompts also will cancel the mailing.[ToC]

USENET News posting

While reading *news articles with Lynx you should see a link that says Reply to: user@host and, if the nntp server from which you received the article supports posting from your site, a link that says Followup to: newsgroup(s)
Reply to user@host
user@host will correspond to 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.
Followup to newsgroup(s)
Selecting this link will allow you to post back to the newsgroup that you are currently reading and any newsgroups to which the message was cross-posted. You will be given the option of including the original message in your reply. Once you have typed in your message, you will be asked for confirmation of whether to proceed with the posting, and whether to append your signature file if one was defined in lynx.cfg and is accessible. See Supported URLs for more information about the URL schemes for posting or sending followups (replies) to nntp servers with Lynx. [ToC]

Lynx bookmarks

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:

Save D)ocument or L)ink to bookmark file or C)ancel? (d,l,c):
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 saving anything to your bookmark file.

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. You can remove a link from the bookmark list by pressing the 'r' key when positioned on that link.

When multi-bookmarks (see Options Menu) is OFF, you will always view or add links to the default bookmark file. When it is STANDARD, a menu of up to 26 bookmark files will be invoked, and you select the bookmark file by entering its letter token. When it is ADVANCED, you will be prompted for the letter token, but can enter '=' to invoke the STANDARD selection menu, or RETURN for the default bookmark file. [ToC]

Jump Command

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 names available.

All jump shortcut entries are saved in a circular buffer, and any previous entries can be retrieved for re-use by pressing the up-arrow or down-arrow keys at the prompt.

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. [ToC]

Directory Editing

Lynx offers extended DIRED support on Unix (on VMS the more powerful CSwing program is recommended for character cell terminals, and can be offered via Lynx as a jump shortcut or execution link). 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
C)reate
Type 'c' to create a new file. New file will be empty.
D)ownload
Type 'd' to download selection using one of the options defined by your system administrator.
E)dit
Type 'e' to spawn the editor defined in Options Menu and load a selected file for editing.
F)ull Menu
Type 'f' to show full menu of options available for selection. Menu may vary according to type of file selected and compression facilities available.
M)odify
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.
R)emove
Type 'r' to remove the selected file or directory.
T)ag
Type 't' to tag highlighted file. Further operations will be performed on tagged files instead of highlighted ones.
U)pload
Type 'u' to upload a file to the present directory. Upload methods are defined by your system administrator.
[ToC]

Scrolling and Other useful commands

A summary of all the keystroke commands and their key bindings can be invoked via the KEYMAP command, normally mapped to 'k' and 'K'. The following describes some of the most commonly used commands.
^A
Control-A jumps you to the beginning of the current document. It is a synonym for the Keypad Home key, and can be used when Links are numbered mode is on. The Find Function key also is a synonym, and ideally the latter has been mapped to the Function key labeled Home if you are using an IBM Enhanced Keyboard.
^E
Control-E jumps you to the end of the current document. It is a synonym for the Keypad End key, and can be used when Links are numbered mode is on. The Select Function key also is a synonym, and ideally the latter has been mapped to the Function key labeled End if you are using an IBM Enhanced Keyboard.
^B
Control-B normally jumps you to the previous page of the current document, and thus is a synonym for the Keypad and Function Page-Up keys. However, Control-B acts as right-arrow when emacs-like key movement is enabled (see Lynx Options Menu).
^F
Control-F normally jumps you to the next page of the current document, and thus is a synonym for the Keypad and Function Page-Down keys. However, Control-F becomes right-arrow when emacs-like key movement is enabled.
^N
Control-N normally jumps you forward two lines in the current document. The Remove Function key (labeled Delete on IBM Enhanced keyboards, and distinct from their Backspace key) is a synonym. Control-N becomes down-arrow when emacs-like key movement is enabled.
^P
Control-P normally jumps you back two lines in the current document. The Insert Function key is a synonym. Control-P becomes up-arrow when emacs-like key movement is enabled.
)
The ) command jumps you forward half a page in the current document.
(
The ( command jumps you back half a page in the current document.
#
The '#' command jumps you to the pseudo Toolbar or Banner if present in the current document. Use left-arrow to return from there to your previous position in the document.
!
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. On VMS, '$' normally is a synonym.
g
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. All previously entered goto URLs are saved in a circular buffer, and can be accessed at the prompt by pressing the up-arrow or down-arrow keys.
G
The 'G' command allows you to edit the URL of the current document and then use that as a goto URL. Pressing the 'G' command will bring up a prompt asking you to edit the current document's URL. If you do not modify it, or completely delete it, or enter Control-G, the command will be cancelled. If the current document has POST content associated with it, an Alert will be issued. If you do edit that URL, and it does not simply involve a fragment change (for seeking a position in the current document), the modified URL will be submitted with method GET and no POST content. If a modification of the current document's URL results in a submission, that modified URL will be entered into the circular buffer for goto URLs, and can be accessed for further modification via the 'g' command.
=
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.
^T
Control-T toggles trace mode on and off. This is useful for diagnosing bad html. If you get a Bad HTML statusline message when loading a document, enter Control-T and then Control-R to reload the document in trace mode. You also can submit the document for validation via links in the online help menu. If you are able to diagnose the problem, send a message about it to the document's author.
*
The '*' command toggles image_links mode on and off. When on, links will be created for all images, including inlines. If you have an image viewer mapped to the image's MIME type, you can activate such links to view an inline image. You should normally have this mode toggled off.
@
The '@' command toggles raw 8-bit or CJK mode on and off. When on, the charset is assumed to match the selected character set and 8-bit characters are not reverse translated with respect to the ISO-8859-1 conversion tables.
[
The '[' command toggles pseudo_inlines mode on and off. When on, inline images which have no ALT string specified will have an [INLINE] pseudo-ALT string inserted in the Lynx display. When off, they will be treated as having ALT="" (i.e., they'll be ignored). If image_links mode is toggled on, the pseudo-ALT strings will be restored, to serve as links to the inline images' sources.
]
The ']' command is used to send HEAD requests for the current document or link. It applies only to documents or links (or form submit buttons) of http servers. A statusline message will notify you if the context for this command was inappropriate. The HEAD requests always are sent to the http server, i.e., Lynx does not retrieve any previous server replies from its cache. Note that for form submissions, http servers vary in whether they'll treat HEAD requests as valid and return the CGI script's headers, or treat it as invalid and return an error message.
^K
Control-K invokes the Cookie Jar Page if it contains cookies.
z
Lynx supports completely interruptible 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 and HTML Forms

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.

An HTML Form provides for the use of buttons to perform an action (such as submit), checkboxes, radio buttons or popups to select options from a list, and fields for entering text.

Buttons:
Buttons are displayed in the same way that Lynx displays links in a document. To "push" the button press the right-arrow or Return key. If it is a form submission button, you also can use the RESUBMIT ('x') or DOWNLOAD ('d') keystroke commands to "push" the button (see below).
Checkboxes and Radio buttons
Checkboxes are displayed as square brackets: [ ] and radio buttons are displayed as parenthesis: ( ). When a box is checked or a button selected, an x appears in the brackets: [x] or 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 the right-arrow or Return key. A box with a border of asterisks (or line-drawing characters) will pop up with the list of possible options listed within the box. Use the up-arrow, down-arrow, page-up, page-down, and other navigation keys to move the cursor among options, and the right-arrow or Return key to select an option. You also can use the '/' and 'n'ext searching commands for navigating to options which contain particular strings. NOTE that the popup menu feature can be disabled via compilation and/or configuration options, or via the Options Menu, in which case the selection field options will be converted to a list of radio buttons. The default setting for use of popups or radio button lists can be toggled via the -popup command line switch.
Text Entry Fields
Text entry (INPUT) 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 Line Editor keys to correct errors. If you try to input more text than the field can hold, the line editor will not accept the additional characters. If you fill a text field the cursor will not move off the field but remain at the last field position. Use the up-arrow, and down-arrow, TAB or Return keys to move up, or down from the text entry field. NOTE, however, that Return also will submit the form if the text entry field is the only non-hidden field in the form.
TEXTAREA fields are handled as if they were a series of text entry (INPUT) fields for which successive lines imply a newline at the end of the preceding line. You enter text on each line to construct the overall message. Any blank lines at the bottom of the TEXTAREA field will be eliminated from the submission. The up-arrow, and down-arrow or Return keys move you to the preceding, or next line of the overall message, as for INPUT fields, and the TAB key will move you down beyond the bottom of the TEXTAREA field, or to the first line on the next page if the overall field extends beyond the currently displayed page.
In general, you can move around the form using the standard Lynx navigation keys. The up-arrow and down-arrow keys, respectively, select the previous or next field, box, or button. The TAB key selects the next field (or next page of a TEXTAREA if it extends onto the next page), box, or button.

NOTE: If you have a text input field selected you will not have access to most of the Lynx keystroke commands, because they are interpreted by the Line Editor as either text entries or editing commands. Select a button or box when you want to use Lynx keystrokes.

To submit the form press right-arrow or Return when positioned on the form's submit button. If you've submitted the form previously during the Lynx session, have not changed any of the form content, and the METHOD was GET, Lynx will retrieve from its cache what was returned from the previous submission. If you wish to resubmit that form to the server with the same content as previously, use the RESUBMIT command ('x') when positioned on the submit button. The right-arrow and Return keys also will invoke a no-cache resubmission if the reply from a form submission included a META element with a no-cache Pragma or Cache-Control directive:
<META HTTP-EQUIV="Pragma" CONTENT="no-cache">
<META HTTP-EQUIV="Cache-Control" CONTENT="no-cache">
or the server sent a "Pragma" or "Cache-Control" MIME header with a no-cache directive.

You also can use the DOWNLOAD ('d') keystroke command when positioned on a form submit button if you wish to download the server's reply to the submission instead of having Lynx render and display it.

Forms which have POST as the METHOD, or a mailto: URL as the ACTION, are always resubmitted, even if the content has not changed, when you activate the submit button. Lynx normally will not resubmit a form which has POST as the METHOD if the document returned by the form has links which you activated, and then you go back via the PREV_DOC (left-arrow) command or via the History Page. Lynx can be compiled so that it resubmits the form in those cases as well, and the default can be changed via lynx.cfg, and toggled via the -resubmit_posts command line switch.

If the form has one text entry field and no other fields except, possibly, hidden INPUT fields not included in the display, then that field also serves as a submit button, and pressing right-arrow or Return on that field will invoke submission of the form. Be sure to use up-arrow, down-arrow or TAB to move off the text entry field, in such cases, if it is not your intention to submit the form (or to retrieve what was returned from an earlier submission if the content was not changed and the METHOD was GET).

Forms can have multiple submit buttons, if they have been assigned NAMEs in the markup. In such cases, information about which one of the buttons was used to submit the form is included in the form content.

Inlined images can be used as submit buttons in forms. If such buttons are assigned NAMEs in the markup, for graphic clients they can also serve as image maps, and the x,y coordinates of the graphic client's cursor position in the image when it was clicked are included in the form content. Since Lynx cannot inline the image, and the user could not have moved a cursor from the origin for the image, if no alternatives are made available in the markup Lynx sends a 0,0 coordinate pair in the form content. Document authors who use images as submit buttons, but have at least some concern for text clients and sight-challenged Webizens, should include VALUEs for the buttons in such markup. Lynx will then display the string assigned to the VALUE, as it would for a normal submit button. Some document authors incorrectly use an ALT instead of VALUE attribute for this purpose. Lynx "cooperates" by treating ALT as a synonym for VALUE when present in an INPUT tag with TYPE="image". If neither a VALUE nor an ALT attribute is present, Lynx displays "[IMAGE]-Submit" as the string for such buttons. If clickable images is set, the "[IMAGE]" portion of the string is a link for the image, and the "Submit" portion is the button for submitting the form. Otherwise, the entire string is treated as a submit button. If a VALUE or ALT attribute is present and clickable images is set, Lynx prepends "[IMAGE]" as a link for the image, followed by '-' and then the attribute's value as the displayed string for the submit button. Note that earlier versions of Lynx would send a name=value pair instead of a 0,0 coordinate pair if a TYPE="image" submit button was NAME-ed, had a VALUE attribute in the INPUT tag, and was used to submit the form. The script which analyzes the form content thus could be made aware whether the submission was by a user with a graphic client and had image loading turned on, or by a user who did not see the image nor make a conscious choice within it. However, requests that this be included in HTML specifications consistently have fallen on deaf ears, and thus Lynx now "fakes" a 0,0 coordinate pair whether or not a VALUE or ALT attribute is present in the INPUT tag. Ideally, the script which analyzes the submitted content will treat the 0,0 coordinate pair as an indicator that the user did not see the image and make a conscious choice within it.

Forms can have hidden INPUT fields, which are not displayed, but have NAMEs and VALUEs included in the content. These often are used to keep track of information across a series of related form submissions, but have the potential for including information about the user that might be considered to represent an invasion of privacy. NOTE, in this regard, that Lynx has implemented the *HTML 3.0 DISABLED attribute for all of its form fields. These can be used to keep track of information across submissions, and to cast it unmodifiable in the current form, but keep the user aware that it will be included in the submission.

Forms most commonly are submitted to http servers with the content encoded as ENCTYPE="application/x-www-form-urlencoded" for analysis by a script, and Lynx treats that as the default if no ENCTYPE is specified in the FORM start tag. However, you can specify a mailto URL as the form's ACTION to have the form content sent, instead, to an email address. In such cases, you may wish to specify ENCTYPE="text/plain" in the form markup, so that the content will not be encoded, but remain readable as plain text.

Lynx also supports ENCTYPE="application/sgml-form-urlencoded" for which all reserved characters in the content will be hex escaped, as with application/x-www-form-urlencoded, but semicolons (';') instead of ampersands ('&') will be used as the separator for name=value pairs in the form content. The use of semicolons is preferred for forms with the GET METHOD, because the GET METHOD causes the encoded form content to be appended as a ?searchpart for the form's ACTION, and if such URLs are used in text/html documents or bookmark files without conversion of the ampersands to SGML character references (&amp; or &#38;), their being followed by form field NAMEs which might correspond to SGML entities could lead to corruption of the intended URL.

NOTE, in this regard, that Lynx converts ampersands to &amp; when creating bookmarks, and thus the bookmark links will not be vulnerable to such corruptions. Also NOTE that Lynx allows you to save links in your bookmark file for documents returned by forms with the GET METHOD, and which thus have the content appended as a ?searchpart, but not if the METHOD was POST, because the content would be lost and the link thus would be invalid.

Lynx supports ENCTYPE="multipart/form-data" for sending form content with name=value pairs encoded as multipart sections with individual MIME headers and boundaries. However, Lynx does not yet support INPUTs with TYPE="file" or TYPE="range" and will set the DISABLED attribute for all of the form's fields if any INPUTs with either of those two TYPEs are present, so that the form can't be submitted. Otherwise, Lynx will submit the form with the multipart ENCTYPE.

A Content-Disposition: file; filename=name.suffix header can be used by CGI scripts to set the suggested filename offered by Lynx for 'd'ownload and 'p'rint menu options to save or mail the body returned by the script following submission of a FORM. Otherwise, Lynx uses the last symbolic element in the path for the FORM's ACTION, which is normally the script, itself, or a PATH_INFO field, and thus might be misleading. This also can be done via a META element in any document: <META HTTP-EQUIV="Content-Disposition"
CONTENT="file; filename=name.suffix">

[ToC]

Lynx and HTML Tables

HTML includes markup for creating tables structured as arrays of cells aligned by columns and rows on the displayed page.

Lynx recognizes the TABLE element and all of its associated elements as described in *ftp://ds.internic.net/rfc/rfc1942.txt and will process any ID attributes in the start tags for handling as NAME-ed anchors, but does not create actual tables. Instead, it treats the TR start tag as a collapsible BR (line break), and inserts a collapsible space before the content of each TH and TD start tag. This generally makes all of the content of the table readable, preserves most of the intra-cell organization, and makes all of the links in the table accessible, but any information critically dependent on the column and row alignments intended for the table will be missed.

If inherently tabular data must be presented with Lynx, one can use PRE formatted content, or, if the table includes markup not allowed for PRE content, construct the table using HTML Tabs. An example table using TAB elements is included in the test subdirectory of the Lynx distribution. [ToC]

Lynx and HTML Tabs

Lynx implements the *HTML 3.0 TAB element only when LEFT alignment is in effect. If the alignment is CENTER or RIGHT (JUSTIFY is not yet implemented in Lynx, and is treated as a synonym for LEFT), or if the TAB element indicates a position to the left of the current position on the screen, it is treated as a collapsible space. For purposes of implementing TAB, Lynx treats en units as half a character cell width when specified by the INDENT attribute, and rounds up for odd values (e.g., a value of either 5 or 6 will be treated as three spaces, each the width of a character cell). See the example table using TAB elements in the test subdirectory of the Lynx distribution as a model for using this functionality.

Note that this Users Guide and the Supported URLs page include TAB markup in a manner which degrades gracefully for WWW browsers which do not support it. Toggle to display of source and search for <tab to examine the use of TAB markup in these documents. [ToC]

Lynx and HTML Frames

Some implementations of HTML include markup, primarily designed for graphic clients, that is intended to create an array of simultaneously displayed, independently scrolling windows. Such windows have been termed frames.

Lynx recognizes the Netscape and MicroSoft Explorer FRAME, FRAMESET, and NOFRAMES elements, but is not capable of windowing to create the intended positioning of frames. Instead, Lynx creates labeled links to the frame sources, typically positioned in the upper left corner of the display, and renders the NOFRAMES section. If the document provider has disregard for text clients and sight-challenged Webizens, and thus does not include substantive content in the NOFRAMES section or a link in it to a document suitable for text clients, you can usually guess from the labeling of the frame links which one has the substantive material (if there is any), or you can try each of those links to see if anything worthwhile is returned. [ToC]

Lynx and HTML Banners

Some implementations of HTML markup include provisions for creating a non-scrolling window to be positioned at the top of each page, containing links with brief, descriptive link names, analogous to a Windows toolbar. Such windows have been termed banners.

Lynx recognizes and processes all of the *HTML 3.0 REL attribute tokens in LINK elements for creating a banner, and a number of others which have subsequently been proposed. These banner tokens are Home, ToC, Contents, Index, Glossary, Copyright, Up, Next, Previous, Prev, Help, Search, Top, Origin, Navigator, Child, Disclaimer, Sibling, Parent, Author, Editor, Publisher, Trademark, Meta, URC, Hotlist, Begin, First, End, Last, Pointer, Translation, Definition, Chapter, Documentation, Biblioentry, Bibliography, Bookmark and Banner. Any LINK elements with those tokens as the REL attribute value, and an HREF attribute value in the LINK, will invoke creation of a banner at the top of the first page, with the element's HREF as the link, and the token as the default link name. If a TITLE attribute is included in the LINK, it's value will be used as the link name instead of the default. Bookmark and Banner are intended to be accompanied by a TITLE attribute, which in effect makes the namespace for REL banner tokens infinite.

If the special token Help is used as the REL value and no HREF is included in the LINK, Lynx will use it own HELPFILE URL for that link. For the special token Home without an HREF, Lynx will use the default STARTFILE (i.e., derived from the configuration files or the WWW_HOME environment variable, not the command line startfile if one was used). However, if a -homepage=URL was specified on the command line, it's URL will be used as the HREF. For the special token Index without an HREF, Lynx will use the DEFAULT_INDEX_FILE derived from the configuration files, or if an -index=URL was specified on the command line, it's URL will be used as the HREF.

Lynx does not waste screen real estate maintaining the banner at the top of every page, but the Lynx TOOLBAR keystroke command ('#') will, any time it is pressed, position you on the banner so that any of its links can be activated, and pressing the left-arrow when in the banner will return you to where you were in the current document. The toolbar is indicated by a '#" preceding its first link when present on the screen, that is, when the first page of the document is being displayed. The availability of a toolbar is indicated by a '#' at the top, left-hand corner of the screen when the second or subsequent pages of the document are being displayed.

Lynx also recognizes the *HTML 3.0 BANNER container element, and will create a banner based on its content if one has not already been created based on LINK elements. Lynx treats the MicroSoft MARQUEE element as a synonym for BANNER (i.e., presenting it's markup as a static banner, without any horizontal scrolling of its content). Lynx does not prefix the BANNER or MARQUEE content with a '#' because the content need not be only a series of links with brief, descriptive links names, but does add a '#' at the top, left-hand corner of the screen when the content is not being displayed, to indicate it's accessibility via the TOOLBAR keystroke command. [ToC]

Lynx and HTML Footnotes

Lynx implements the *HTML 3.0 FN element similarly to a named Anchor within the current document, and assumes that the footnotes will be positioned at the bottom of the document. However, in contrast to named Anchors, the FN container element is treated as a block (i.e., as if a new paragraph were indicated whether or not that is indicated in its content) with greater than normal left and right margins, and the block will begin with a FOOTNOTE: label. For example, if the document contains:
See the <A HREF="#fn1">footnote</A>.
activating that link will take you to the labeled rendering of:

<FN ID="fn1"><p>Lynx does not use popups for FN blocks.</p></FN>

i.e., position it at the top of the page. Then, upon reading the footnote, you can return to your previous position in the document by pressing the left-arrow key. The content of an FN element can be any HTML markup that is valid in the BODY of the document. [ToC]

Lynx and HTML Notes

Lynx implements the *HTML 3.0 NOTE element (Admonishment) as a labeled block, i.e., as if a new paragraph were indicated whether or not paragraphing markup is included in its content, with greater than normal left and right margins, and with the type of note indicated by an emphasized label based on the value of its CLASS or ROLE attribute. If no CLASS or ROLE attribute is included, the default label NOTE: will be used. Lynx recognizes the values caution and warning, for which, respectively, the labels CAUTION: or WARNING: will be used. The NOTE element can have an ID attribute, which will be treated as a named Anchor, as for HTML Footnotes, but the NOTE block need not be placed at the bottom of the document. The content of a NOTE block can be any HTML markup that is valid in the BODY of the document. This is an example:
<NOTE CLASS="warning" ID="too-bad">
<p>The W3C vendors did not retain NOTE in the HTML 3.2 draft.</p>
</NOTE>

It will degrade gracefully for WWW browsers which do not support NOTE, except for recognition of the ID attribute as a named Anchor. [ToC]

Lynx and HTML Lists

Lynx implements the *HTML 3.0 list elements UL (Unordered List), OL (Ordered List), and DL (Definition List), and their associated attributes, and elements (LH, LI, DT, and DD) for the most part as described in that specification. The lists can be nested, yielding progressively greater indentation, up to six levels. The *HTML 2.0 MENU and DIR elements both are treated as synonyms for UL with the PLAIN attribute (no bullets, see below). Note, thus, that neither DIR nor MENU yields a series of columns with 24-character spacing. A single nesting index is maintained, so that different types of List elements can be used for different levels within the nest. Also, the *HTML 3.0 FIG, CAPTION and CREDIT elements are treated as valid within list blocks. They will be rendered with indentation appropriate for the current nesting depth, and the CAPTION or CREDIT elements will have a CAPTION: or CREDIT: label beginning the first line of their content. The content of any APPLET or OBJECT elements in the lists also will be indented appropriately for the current nesting depth, but those will not invoke line breaks unless indicated by their content, and it should not include markup which is inappropriate within the list.

Lynx also supports the TYPE attribute for OL elements, which can have values of 1 for Arabic numbers, I or i for uppercase or lowercase Roman numerals, or A or a for uppercase or lowercase letters, that increment for successive LI elements in the list block. The CONTINUE attribute can be used to continue the ordering from the preceding list block when the nesting depth is changed.

Lynx treats the OL attributes START and SEQNUM as synonyms for specifying the ordering value for the first LI element in the block. The values should be specified as Arabic numbers, but will be displayed as Arabic, Roman, or alphabetical depending on the TYPE for the block. The values can range from -29997 to the system's maximum positive integer for Arabic numbers. For Roman numerals, they can range from 1 (I or i) to 3000 (MMM or mmm.). For alphabetical orders, the values can range from 1 (A or a) to 18278 (ZZZ or zzz). If the CONTINUE attribute is used, you do not need to specify a START or SEQNUM attribute to extend the ordering from a previous block, and you can include a TYPE attribute to change among Arabic, Roman, or alphabetical ordering styles, or their casing, without disrupting the sequence. If you do not include a START, SEQNUM or CONTINUE attribute, the first LI element of each OL block will default to 1, and if you do not include a TYPE attribute, Lynx defaults to Arabic numbers.

For UL blocks without the PLAIN attribute, Lynx uses *, +, o, #, @ and - as bullets to indicate, progressively, the depth within the six nesting levels.

Lynx treats UL, OL, DIR, and MENU blocks as having the COMPACT attribute by default, i.e., single spaces between LH and LI elements within those blocks. For DL blocks, double spacing will be used to separate the DT and DD elements unless the COMPACT attribute has been specified. [ToC]

Lynx and HTML Quotes

The *HTML 3.0 and later specifications provide for two classes of quotation in HTML documents. Block quotes, designated by the BLOCKQUOTE element (or it's abbreviated synonym BQ in HTML 3.0), have implied paragraph breaks preceding and following the start and end tags for the block. Character level quotes, designated by the Q element, in contrast are simply directives in the markup to insert an appropriate quotation mark.

Lynx renders block quotes with a greater than normal left and right indentation. Lynx does not support italics, and normally substitutes underlining, but does not underline block quotes so as not to obscure any explicit emphasis elements within the quotation. The BLOCKQUOTE or BQ block can include a CREDIT container element, whose content will be rendered as an implied new paragraph with a CREDIT: label at the beginning of its first line.

Lynx respects nested Q start and end tags, and will use ASCII double-quotes (") versus grave accent (`) and apostrophe ('), respectively, for even versus odd depths in the nest.

Any ID attributes in BLOCKQUOTE, BQ or Q elements will be treated as named Anchors. [ToC]

Lynx and Client-Side-Image-Maps

HTML includes markup, designed primarily for graphic clients, that treats inlined images as maps, such that areas of the image within which a mouse cursor was positioned when the mouse was clicked can correspond to URLs which should be retrieved. The original implementations were based on the client sending an http server the x,y coordinates associated with the click, for handling by a script invoked by the server, and have been termed server-side-image-maps. Lynx has no rational way of coping with such a procedure, and thus simply sends a 0,0 coordinate pair, which some server scripts treat as an instruction to return a document suitable for a text client.

Newer HTML markup provides bases for the client to determine the URLs associated with areas in the image map, and/or for a text client to process alternative markup and allow the user to make choices based on textual information. These have been termed client-side-image-maps.

Lynx recognizes and processes the MAP container element and its AREA elements, and will create a menu of links for the HREF of each AREA when the link created for the IMG element with a USEMAP attribute is activated. The menu uses the ALT attributes of the AREA elements as the link names, or, if the document's author has disregard for text clients and sight-challenged Webizens, and thus did not include ALT attributes, Lynx uses the resolved URLs pointed to by the HREF attributes as the link names. Lynx uses the TITLE attribute of the IMG element, or the TITLE attribute of the MAP, if either was present in the markup, as the title and main header of the menu. Otherwise, it uses the ALT attribute of the IMG element. If neither TITLE nor ALT attributes were present in the markup, Lynx creates and uses a [USEMAP] pseudo-ALT. The MAPs need not be in the same document as the IMG elements. If not in the same document, Lynx will fetch the document which contains the referenced MAP, and locate it based on its NAME or ID attribute. All MAPs encountered in documents during a Lynx session are cached, so that they need not be retrieved repeatedly when referenced in different documents.

If the IMG element also indicates a server-side-image-map via an ISMAP attribute, Lynx will create a link for that as well, rather than ignoring it, and will submit a 0,0 coordinate pair if that link is activated. However, the client-side-image-map is much more useful for a client such as Lynx, because all of the URLs associated with the image map can be accessed, and their nature indicated via ALT attributes.

Lynx also recognizes the *HTML 3.0 FIG and OVERLAY elements, and will handle them as intended for text clients. These are the ideal way to handle client-side-image-maps, because the FIG content provides complete alternative markup, rather than relying on the client to construct a relatively meager list of links with link names based on ALT strings.

The presently experimental OBJECT element encompasses much of the functionality of the FIG element for client-side-image-maps. Lynx will render and display the content of OBJECT elements which have the SHAPES attribute equivalently to its handling of FIG. Lynx also handles OBJECT elements with the USEMAP and/or ISMAP attributes equivalently to its handling of IMG elements with client-side-image-maps and/or server-side-image-maps. [ToC]

Lynx and Client-Side-Pull

HTML includes provision for passing instructions to clients via directives in META elements, and one such instruction, via the token Refresh, should invoke reloading of the document, fetched from a server with the same URL or a new URL, at a specified number of seconds following receipt of the current document. This procedure has been termed client-side-pull. An example of such an element is:
<META HTTP-EQUIV="Refresh" CONTENT="3; URL="http://host/path">
which instructs a client to fetch the indicated URL in 3 seconds after receiving the current document. If the URL= field is omitted, the URL defaults to that of the current document. A no-cache directive is implied when the Refresh if for the same URL.

Lynx recognizes and processes Refresh directives in META elements, but puts up a labeled link, typically in the upper left corner of the display, indicating the number of seconds intended before a refresh, and the URL for the refresh, instead of making the request automatically after the indicated number of seconds. This allows people using a braille interface any amount of time to examine the current document before activating the link for the next URL. In general, if the number of seconds indicated is short, the timing is not critical and you can activate the link whenever you like. If it is long (e.g., 60 seconds), a server process may be generating new documents or images at that interval, and you would be wasting bandwidth by activating the link at a shorter interval. [ToC]

Lynx State Management (Me want cookie!)

HTTP provides a means to carry state information across successive connections between a browser and an http server. Normally, http servers respond to each browser request without relating that request to previous or subsequent requests. Though the inclusion of INPUT fields with TYPE="hidden" can be used as a sort of state management by HTML Forms, a more general approach involves exchanges of MIME headers between the server and browser. When replying to a request, the server can send a Set-Cookie MIME header which contains information (cookies) relevant to the browser's request, and in subsequent requests the browser can send a Cookie MIME header with information derived from previously received cookies.

State Management via cookie exchanges originally was implemented by Netscape, and such cookies are now designated as Version 0. A more elaborate format for cookies, designated as Version 1, is being standardized by the IETF (Internet Engineering Task Force). Lynx supports both Version 0 and Version 1 cookie exchanges. This support can be disabled by default via the SET_COOKIES symbol in the compilation (userdefs.h) and/or run time (lynx.cfg) configuration files, and that default setting can be toggled via the -cookies command line switch.

When cookie support is enabled, Set-Cookie MIME headers received from an http server invoke confirmation prompts with possible replies of 'Y'es or 'N'o for acceptance of the cookie, 'A'lways to accept the cookie and to allow all subsequent cookies from that domain (server's Fully Qualified Domain Name, or site-identifying portion of the FQDN) without further confirmation prompts, or ne'V'er to never allow cookies from that domain to be accepted (silently ignore its Set-Cookie MIME headers). All unexpired cookies are held in a hypothetical Cookie Jar which can be examined via the COOKIE_JAR keystroke command, normally mapped to Ctrl-K, for invoking the Cookie Jar Page. The Cookie Jar, and any 'A'lways or ne'V'er 'allow' settings, do not presently outlast the Lynx session.

A common use of cookies by http servers is simply to track the documents visited by individual users. Though this can be useful to the site's WebMaster for evaluating and improving the organization of links in the various documents of the site, if the user has configured Lynx to include a From MIME header with the user's email address in http requests, or has passed personal information to the server via a form submission, the tracking might be used to draw inferences, possibly incorrect, about that user, and may be considered by some as an invasion of privacy.

An example of worthwhile State Management via cookies is the setting of personal preferences, typically via a form submission to the site, which will then apply to all documents visited at that site.

If you accept cookies when accessing a site, but are given no indication about how they will be used in subsequent requests to that site, nor can infer how they will be used, you can Gobble (delete) the cookies and/or change the 'allow' setting for its domain via the Cookie Jar Page. [ToC]

The Lynx command line

A summary of the Lynx command line options (switches) is returned to stdout if Lynx is invoked with the -help switch. A description of the options also should be available via the system man (Unix) pages or help (VMS) libraries. The basic syntax of the Lynx command line can be represented as one of the following:
Command
lynx [options]
lynx [options] startfile
where
startfile
is the file or URL that Lynx will load at start-up.
  • If startfile is not 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.
options
can be selected from the following list, where items in all-caps indicate that a substitution must be made.
-
If the only argument is '-' (dash), then Lynx expects to receive the arguments from stdin. This is to allow for the potentially very long command line that can be associated with the -get_data or -post_data arguments (see below). On VMS, it must be encased in double-quotes ("-") and the keyboard input terminated with Control-Z or the command file input terminated by a line that begins with '$'.
-anonymous
used to specify the anonymous account.
-auth=ID:PW
id and password for protected pages.
-base
prepend a request URL comment and BASE tag to text/html outputs for -source or -mime_header dumps.
-book
use the bookmark page as the startfile. The default or command line startfile is still set for the Main screen command, and will be used if the bookmark page is unavailable or blank.
-buried_news
toggles scanning of news articles for buried references, and converts them to news links. Not recommended because email addresses enclosed in angle brackets will be converted to false news links, and uuencoded messages can be trashed.
-cache=NUMBER
set the NUMBER of documents cached in memory. The default is 10.
-case
enable case-sensitive string searching.
-cfg=FILENAME
specifies a Lynx configuration file other than the default lynx.cfg.
-child
exit on left-arrow in startfile, and disable save to disk.
-cookies
toggles handling of Set-Cookie headers.
-crawl
with -traversal, output each page to a file.
with -dump, format output as with -traversal, but to stdout.
-display=DISPLAY
set the display variable for X rexe-ced programs.
-dump
dumps the formatted output of the default document or one specified on the command line to standard out. This can be used in the following way:
lynx -dump http://www.w3.org/
-editor=EDITOR
enable edit mode using the specified EDITOR. (vi, ed, emacs, etc.)
-emacskeys
enable emacs-like key movement.
-enable_scrollback
toggles behavior compatible with the scrollback keys in some communications software (may be incompatible with some curses packages).
-error_file=FILENAME
the status code from the HTTP request is placed in this file.
-locexec
enable local program execution from local files only (if lynx was compiled with local execution enabled).
-fileversions
include all versions of files in local VMS directory listings.
-force_html
forces the first document to be interpreted as HTML.
-ftp
disable ftp access.
-get_data
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 '---'.
-head
send a HEAD request for the mime headers.
-help
print this Lynx command syntax usage message.
-historical
toggles use of '>' or '-->' as a terminator for comments.
-homepage=URL
set homepage separate from start page. Will be used if a fetch of the start page fails or if it is a script which does not return a document, and as the URL for the 'm'ain menu command.
-image_links
toggles inclusion of links for all images.
-index=URL
set the default index file to the specified URL
-link=NUMBER
starting count for lnk#.dat files produced by -crawl.
-localhost
disable URLs that point to remote hosts.
-mime_header
include mime headers and force source dump.
-minimal
toggles minimal versus valid comment parsing. When minimal, any '-->' serves as a terminator for a comment element. When valid, pairs of '--' are treated as delimiters for series of comments within the overall comment element. If historical is set, that overrides minimal or valid comment parsing.
-newschunksize=NUMBER
number of articles in chunked news listings.
-newsmaxchunk=NUMBER
maximum news articles in listings before chunking.
-nobrowse
disable directory browsing.
-noexec
disable local program execution. (DEFAULT)
-nofilereferer
disable transmissions of Referer headers for file URLs.
-nofrom
disable transmissions of From headers.
-nolist
disable the link list feature in dumps.
-nolog
disable mailing of error messages to document owners.
-nopause
disable forced pauses for statusline messages.
-noprint
disable print functions.
-noredir
don't follow URL redirections
-noreferer
disable transmissions of Referer headers.
-nosocks
disable SOCKS proxy usage by a SOCKSified Lynx.
-nostatus
disable the retrieval status messages.
-number_links
force numbering of links.
-popup
toggles handling of single-choice SELECT options via popup windows or as lists of radio buttons.
-post_data
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 '---'.
-print
enable print functions. (default)
-pseudo_inlines
toggles pseudo-ALTs for inlines with no ALT string.
-raw
toggles default setting of 8-bit character translations or CJK mode for the startup character set.
-realm
restricts access to URLs in the starting realm.
-reload
flushes the cache on a proxy server (only the first document affected).
-restrictions
allows a list of services to be disabled selectively and takes the following form:
lynx -restrictions=[option][,option][,option]...
This list is printed if no options are specified.
all
restricts all options.
bookmark
disallow changing the location of the bookmark file.
bookmark_exec
disallow execution links via the bookmark file.
change_exec_perms
disallow changing the eXecute permission on files (but still allow it for directories) when local file management is enabled.
default
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 settable within userdefs.h.
dired_support
disallow local file management.
disk_save
disallow saving binary files to disk in the download menu.
download
disallow downloaders in the download menu.
editor
disallow editing.
exec
disable execution scripts.
exec_frozen
disallow the user from changing the local execution option.
file_url
disallow using G)oto, served links or bookmarks for file: URLs.
goto
disable the 'g' (goto) command.
inside_ftp
disallow ftps for people coming from inside your domain.
inside_news
disallow USENET news posting for people coming from inside you domain.
inside_rlogin
disallow rlogins for people coming from inside your domain.
inside_telnet
disallow telnets for people coming from inside your domain.
jump
disable the 'j' (jump) command.
mail
disallow mailing feature.
multibook
disallow multiple bookmarks.
news_post
disallow USENET News posting.
options_save
disallow saving options in .lynxrc.
outside_ftp
disallow ftps for people coming from outside your domain.
outside_news
disallow USENET news posting for people coming from outside you domain.
outside_rlogin
disallow rlogins for people coming from outside your domain.
outside_telnet
disallow telnets for people coming from outside your domain.
print
disallow most print options.
shell
disallow shell escapes.
suspend
disallow Control-Z suspends with escape to shell on Unix.
telnet_port
disallow specifying a port in telnet G)oto's.
useragent
disallow modifications of the User-Agent header.
-resubmit_posts
toggles forced resubmissions (no-cache) of forms with method POST when the documents they returned are sought with the PREV_DOC (left-arrow) command or from the History Page.
-rlogin
disable recognition of rlogin commands.
-selective
require .www_browsable files to browse directories.
-show_cursor
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. The default configuration can be changed in userdefs.h or lynx.cfg. The command line switch toggles the default.
-soft_dquotes
toggles emulation of the old Netscape and Mosaic bug which treated '>' as a co-terminator for double-quotes and tags.
-source
works the same as dump but outputs HTML source instead of formatted text.
-startfile_ok
allow non-http startfile and homepage with -validate.
-telnet
disable recognition of telnet commands.
-term=TERM
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.)
-trace
turns on WWW trace mode.
-traversal
traverse all http links derived from startfile. When used with -crawl, each link that begins with the same string as startfile is output to a file, intended for indexing. See CRAWL.announce for more information.
-underscore
toggles use of _underline_ format in dumps.
-validate
accept only http URLs (for validation). Complete security restrictions also are implemented.
-version
print version information
-vikeys
enable vi-like key movement.

No options are required, nor is a startfile argument required. White space may be substituted for any equal sign ('=') appearing in the option list above. [ToC]

Lynx development history

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 (Unix 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 Unix, VMS, VM/CMS and Macintosh). In addition, Lynx became the most user-friendly Gopher client, although that was only an ancillary capability.

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 providers.

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 capabilities offered in the curses environment.

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 and Craig Lavender.

Foteos Macrides and members of the lynx-dev list have developed and supported Lynx since release of v2.3 in May 1994. The Lynx2-3FM code set was released as v2.4 in June 1995. The Lynx2-4FM code set was released as v2.5 in May 1996. The Lynx2-5FM code set was released as v2.6 in September 1996. The Lynx2-6FM code set was released as v2.7 in February 1997.

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 Unix environment. Those versions also incorporated libraries from the Unix 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.

Information on obtaining the most current version of Lynx is available via *Lynx links.

[ToC]