LYNX

NAME
SYNOPSIS
DESCRIPTION
OPTIONS
COMMANDS
ENVIRONMENT
SIMULATED CGI SUPPORT
NATIVE LANGUAGE SUPPORT
NOTES
SEE ALSO
ACKNOWLEDGMENTS
AUTHORS

NAME

lynx − a general purpose distributed information browser for the World Wide Web

SYNOPSIS

lynx [options] [path or URL]

use "lynx -help" to display a complete list of current options.

DESCRIPTION

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 Windows 95/NT or Macintoshes, 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, VMS, Windows 95/NT, 386DOS and OS/2 EMX.

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.

OPTIONS

At start up, Lynx will load any local file or remote URL specified at the command line. For help with URLs, press "?" or "H" while running Lynx. Then follow the link titled, "Help on URLs."

Lynx uses only long option names. Option names can begin with double dash as well, underscores and dashes can be intermixed in option names (in the reference below options are with one dash before them and with underscores).

-

If the argument is only ’-’, 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). It can also be used to avoid having sensitive information in the invoking command line (which would be visible to other processes on most systems), especially when the -auth or -pauth options are used.

-accept_all_cookies

accept all cookies.

-anonymous

apply restrictions for anonymous account, see also -restrictions.

-assume_charset=MIMEname

charset for documents that don’t specify it.

-assume_local_charset=MIMEname

charset assumed for local files.

-assume_unrec_charset=MIMEname

use this instead of unrecognized charsets.

-auth=ID:PASSWD

set authorization ID and password for protected documents at startup. Be sure to protect any script files which use this switch.

-base

prepend a request URL comment and BASE tag to text/html outputs for -source dumps.

-blink

forces high intensity background colors for color mode, if available and supported by the terminal. Lynx needs to be compiled with the slang library for this flag.

-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.

-color

forces color mode on, if available. Default color control sequences which work for many terminal types are assumed if the terminal capability description does not specify how to handle color. Lynx needs to be compiled with the slang library for this flag, it is equivalent to setting the COLORTERM environment variable. (If color support is instead provided by a color-capable curses library like ncurses, Lynx relies completely on the terminal description to determine whether color mode is possible, and this flag is not needed and thus unavailable.) A saved show_color=always setting found in a .lynxrc file at startup has the same effect. A saved show_color=never found in .lynxrc on startup is overridden by this flag.

-cookies

toggles handling of Set-Cookie headers.

-cookie_file=FILENAME

specifies a file to use to store cookies.

-core

toggles forced core dumps on fatal errors.

-crawl

with -traversal, output each page to a file. with -dump, format output as with -traversal, but to stdout.

-debug_partial

incremental display stages with MessageSecs delay

-display=DISPLAY

set the display variable for X rexec-ed programs.

-dont_wrap_pre

inhibit wrapping of text in <pre> when -dump’ing and -crawl’ing, mark wrapped lines in interactive session.

-dump

dumps the formatted output of the default document or one specified on the command line to standard output. This can be used in the following way:

lynx -dump http://www.crl.com/~subir/lynx.html

-editor=EDITOR

enable external editing, using the specified EDITOR. (vi, ed, emacs, etc.)

-emacskeys

enable emacs-like key movement.

-enable_scrollback

toggles compatibility with communication programs’ scrollback keys (may be incompatible with some curses packages).

-error_file=FILE

define a file where Lynx will report HTTP access codes.

-exec

enable local program execution (normally not configured).

-fileversions

include all versions of files in local VMS directory listings.

-force_empty_hrefless_a

force HREF-less ’A’ elements to be empty (close them as soon as they are seen).

-force_html

forces the first document to be interpreted as HTML.

-force_secure

toggles forcing of the secure flag for SSL cookies.

-forms_options

toggles whether the Options Menu is key-based or form-based.

-from

toggles transmissions of From headers.

-ftp

disable ftp access.

-get_data

send form data from stdin using GET method and dump results.

-head

send a HEAD request for the mime headers.

-help

print the Lynx command syntax usage message.

-hiddenlinks=[option]

control the display of hidden links.

merge hidden links show up as bracketed numbers and are numbered together with other links in the sequence of their occurrence in the document.

listonly hidden links are shown only on L)ist screens and listings generated by -dump or from the P)rint menu, but appear separately at the end of those lists. This is the default behavior.

ignore hidden links do not appear even in listings.

-historical

toggles use of ’>’ or ’-->’ as a terminator for comments.

-homepage=URL

set homepage separate from start page.

-image_links

toggles inclusion of links for all images.

-index=URL

set the default index file to the specified URL.

-ismap

toggles inclusion of ISMAP links when client-side MAPs are present.

-justify

do justification of text.

-link=NUMBER

starting count for lnk#.dat files produced by -crawl.

-localhost

disable URLs that point to remote hosts.

-locexec

enable local program execution from local files only (if Lynx was compiled with local execution enabled).

-mime_header

prints the MIME header of a fetched document along with its source.

-minimal

toggles minimal versus valid comment parsing.

-newschunksize=NUMBER

number of articles in chunked news listings.

-newsmaxchunk=NUMBER

maximum news articles in listings before chunking.

-nobold

disable bold video-attribute.

-nobrowse

disable directory browsing.

-nocc

disable Cc: prompts for self copies of mailings. Note that this does not disable any CCs which are incorporated within a mailto URL or form ACTION.

-nocolor

force color mode off, overriding terminal capabilities and any -color flags, COLORTERM variable, and saved .lynxrc settings.

-noexec

disable local program execution. (DEFAULT)

-nofilereferer

disable transmissions of Referer headers for file URLs.

-nolist

disable the link list feature in dumps.

-nolog

disable mailing of error messages to document owners.

-nonrestarting_sigwinch

This flag is not available on all systems, Lynx needs to be compiled with HAVE_SIGACTION defined. If available, this flag may cause Lynx to react more immediately to window changes when run within an xterm.

-nopause

disable forced pauses for statusline messages.

-noprint

disable most print functions.

-noredir

prevents automatic redirection and prints a message with a link to the new URL.

-noreferer

disable transmissions of Referer headers.

-noreverse

disable reverse video-attribute.

-nosocks

disable SOCKS proxy usage by a SOCKSified Lynx.

-nostatus

disable the retrieval status messages.

-nounderline

disable underline video-attribute.

-number_fields

force numbering of links as well as form input fields

-number_links

force numbering of links.

-partial

toggles display partial pages while loading.

partial_thres=NUMBER

number of lines to render before repainting display with partial-display logic

-pauth=ID:PASSWD

set authorization ID and password for a protected proxy server at startup. Be sure to protect any script files which use this switch.

-popup

toggles handling of single-choice SELECT options via popup windows or as lists of radio buttons.

-post_data

send form data from stdin using POST method and dump results.

-preparsed

show HTML source preparsed and reformatted when used with -source or in source view.

-prettysrc

show HTML source view with lexical elements and tags in color.

-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=[option][,option][,option]...

allows a list of services to be disabled selectively. Dashes and underscores in option names can be intermixed. The following list is printed if no options are specified.

all - restricts all options listed below.

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. Set to all restricted, except for: inside_telnet, outside_telnet, inside_ftp, outside_ftp, inside_rlogin, outside_rlogin, inside_news, outside_news, telnet_port, jump, mail, print, exec, and goto. The settings for these, as well as additional goto restrictions for specific URL schemes that are also applied, are derived from definitions within userdefs.h.

dired_support - disallow local file management.

disk_save - disallow saving to disk in the download and print menus.

dotfiles - disallow access to, or creation of, hidden (dot) files.

download - disallow some downloaders in the download menu (does not imply disk_save restriction).

editor - disallow external editing.

exec - disable execution scripts.

exec_frozen - disallow the user from changing the local execution option.

externals - disallow some "EXTERNAL" configuration lines if support for passing URLs to external applications (with the EXTERN command) is compiled in.

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 (utmp required for selectivity).

inside_news - disallow USENET news posting for people coming from inside your domain (utmp required for selectivity).

inside_rlogin - disallow rlogins for people coming from inside your domain (utmp required for selectivity).

inside_telnet - disallow telnets for people coming from inside your domain (utmp required for selectivity).

jump - disable the ’j’ (jump) command.

multibook - disallow multiple bookmarks.

mail - disallow mail.

news_post - disallow USENET News posting.

options_save - disallow saving options in .lynxrc.

outside_ftp - disallow ftps for people coming from outside your domain (utmp required for selectivity).

outside_news - disallow USENET news reading and posting for people coming from outside your domain (utmp required for selectivity). This restriction applies to "news", "nntp", "newspost", and "newsreply" URLs, but not to "snews", "snewspost", or "snewsreply" in case they are supported.

outside_rlogin - disallow rlogins for people coming from outside your domain (utmp required for selectivity).

outside_telnet - disallow telnets for people coming from outside your domain (utmp required for selectivity).

print - disallow most print options.

shell - disallow shell escapes and lynxexec or lynxprog G)oto’s.

suspend - disallow Unix Control-Z suspends with escape to shell.

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 command or from the History List.

-rlogin

disable recognition of rlogin commands.

-selective

require .www_browsable files to browse directories.

-short_url

show very long URLs in the status line with "___" to represent the portion which cannot be displayed. The beginning and end of the URL are displayed, rather than suppressing the end.

-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.

-stack_dump

disable SIGINT cleanup handler

-startfile_ok

allow non-http startfile and homepage with -validate.

-tagsoup

initialize parser, using Tag Soup DTD rather than SortaSGML.

-telnet

disable recognition of telnet commands.

-term=TERM

tell Lynx what terminal type to assume it is 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.)

-tlog

toggles between using a Lynx Trace Log and stderr for trace output from the session.

-tna

turns on "Textfields Need Activation" mode.

-trace

turns on Lynx trace mode. Destination of trace output depends on -tlog.

-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.

-use_mouse

turn on mouse support, if available. Clicking the left mouse button on a link traverses it. Clicking the right mouse button pops back. Click on the top line to scroll up. Click on the bottom line to scroll down. The first few positions in the top and bottom line may invoke additional functions. Lynx must be compiled with ncurses or slang to support this feature. If ncurses is used, clicking the middle mouse button pops up a simple menu. Mouse clicks may only work reliably while Lynx is idle waiting for input.

-useragent=Name

set alternate Lynx User-Agent header.

-validate

accept only http URLs (for validation). Complete security restrictions also are implemented.

-verbose

toggle [LINK], [IMAGE] and [INLINE] comments with filenames of these images.

-version

print version information.

-vikeys

enable vi-like key movement.

-wdebug

enable Waterloo tcp/ip packet debug (print to watt debugfile). This applies only to DOS versions compiled with WATTCP or WATT-32.

-width=NUMBER

number of columns for formatting of dumps, default is 80.

-with_backspaces

emit backspaces in output if -dumping or -crawling (like ’man’ does)

COMMANDS

o Use Up arrow and Down arrow to scroll through hypertext links.
o Right arrow or Return will follow a highlighted hypertext link.
o Left Arrow will retreat from a link.
o Type "H" or "?" for online help and descriptions of key-stroke commands.
o Type "K" for a complete list of the current key-stroke command mappings.

ENVIRONMENT

In addition to various "standard" environment variables such as HOME, PATH, USER, DISPLAY, TMPDIR, etc, Lynx utilizes several Lynx-specific environment variables, if they exist.

Others may be created or modified by Lynx to pass data to an external program, or for other reasons. These are listed separately below.

See also the sections on SIMULATED CGI SUPPORT and NATIVE LANGUAGE SUPPORT, below.

Note: Not all environment variables apply to all types of platforms supported by Lynx, though most do. Feedback on platform dependencies is solicited.

Environment Variables Used By Lynx:

COLORTERM

If set, color capability for the terminal is forced on at startup time. The actual value assigned to the variable is ignored. This variable is only meaningful if Lynx was built using the slang screen-handling library.

LYNX_CFG

This variable, if set, will override the default location and name of the global configuration file (normally, lynx.cfg) that was defined by the LYNX_CFG_FILE constant in the userdefs.h file, during installation. See the userdefs.h file for more information.

LYNX_LSS

This variable, if set, specifies the location of the default Lynx character style sheet file. [Currently only meaningful if Lynx was built using experimental color style support.]

LYNX_SAVE_SPACE

This variable, if set, will override the default path prefix for files saved to disk that is defined in the lynx.cfg SAVE_SPACE: statement. See the lynx.cfg file for more information.

LYNX_TEMP_SPACE

This variable, if set, will override the default path prefix for temporary files that was defined during installation, as well as any value that may be assigned to the TMPDIR variable.

MAIL

This variable specifies the default inbox Lynx will check for new mail, if such checking is enabled in the lynx.cfg file.

NEWS_ORGANIZATION

This variable, if set, provides the string used in the Organization: header of USENET news postings. It will override the setting of the ORGANIZATION environment variable, if it is also set (and, on UNIX, the contents of an /etc/organization file, if present).

NNTPSERVER

If set, this variable specifies the default NNTP server that will be used for USENET news reading and posting with Lynx, via news: URL’s.

ORGANIZATION

This variable, if set, provides the string used in the Organization: header of USENET news postings. On UNIX, it will override the contents of an /etc/organization file, if present.

PROTOCOL_proxy

Lynx supports the use of proxy servers that can act as firewall gateways and caching servers. They are preferable to the older gateway servers (see WWW_access_GATEWAY, below). Each protocol used by Lynx, (http, ftp, gopher, etc), can be mapped separately by setting environment variables of the form PROTOCOL_proxy (literally: http_proxy, ftp_proxy, gopher_proxy, etc), to "http://some.server.dom:port/". See Lynx Users Guide for additional details and examples.

WWW_access_GATEWAY

Lynx still supports use of gateway servers, with the servers specified via "WWW_access_GATEWAY" variables (where "access" is lower case and can be "http", "ftp", "gopher" or "wais"), however most gateway servers have been discontinued. Note that you do not include a terminal ’/’ for gateways, but do for proxies specified by PROTOCOL_proxy environment variables. See Lynx Users Guide for details.

WWW_HOME

This variable, if set, will override the default startup URL specified in any of the Lynx configuration files.

Environment Variables Set or Modified By Lynx:

LYNX_PRINT_DATE

This variable is set by the Lynx p(rint) function, to the Date: string seen in the document’s "Information about" page (= cmd), if any. It is created for use by an external program, as defined in a lynx.cfg PRINTER: definition statement. If the field does not exist for the document, the variable is set to a null string under UNIX, or "No Date" under VMS.

LYNX_PRINT_LASTMOD

This variable is set by the Lynx p(rint) function, to the Last Mod: string seen in the document’s "Information about" page (= cmd), if any. It is created for use by an external program, as defined in a lynx.cfg PRINTER: definition statement. If the field does not exist for the document, the variable is set to a null string under UNIX, or "No LastMod" under VMS.

LYNX_PRINT_TITLE

This variable is set by the Lynx p(rint) function, to the Linkname: string seen in the document’s "Information about" page (= cmd), if any. It is created for use by an external program, as defined in a lynx.cfg PRINTER: definition statement. If the field does not exist for the document, the variable is set to a null string under UNIX, or "No Title" under VMS.

LYNX_PRINT_URL

This variable is set by the Lynx p(rint) function, to the URL: string seen in the document’s "Information about" page (= cmd), if any. It is created for use by an external program, as defined in a lynx.cfg PRINTER: definition statement. If the field does not exist for the document, the variable is set to a null string under UNIX, or "No URL" under VMS.

LYNX_VERSION

This variable is always set by Lynx, and may be used by an external program to determine if it was invoked by Lynx. See also the comments in the distribution’s sample mailcap file, for notes on usage in such a file.

TERM

Normally, this variable is used by Lynx to determine the terminal type being used to invoke Lynx. If, however, it is unset at startup time (or has the value "unknown"), or if the -term command-line option is used (see OPTIONS section above), Lynx will set or modify its value to the user specified terminal type (for the Lynx execution environment). Note: If set/modified by Lynx, the values of the LINES and/or COLUMNS environment variables may also be changed.

SIMULATED CGI SUPPORT

If built with the cgi-links option enabled, Lynx allows access to a cgi script directly without the need for an http daemon.

When executing such "lynxcgi scripts" (if enabled), the following variables may be set for simulating a CGI environment:

CONTENT_LENGTH

CONTENT_TYPE

DOCUMENT_ROOT

HTTP_ACCEPT_CHARSET

HTTP_ACCEPT_LANGUAGE

HTTP_USER_AGENT

PATH_INFO

PATH_TRANSLATED

QUERY_STRING

REMOTE_ADDR

REMOTE_HOST

REQUEST_METHOD

SERVER_SOFTWARE

Other environment variables are not inherited by the script, unless they are provided via a LYNXCGI_ENVIRONMENT statement in the configuration file. See the lynx.cfg file, and the (draft) CGI 1.1 Specification <http://Web.Golux.Com/coar/cgi/draft-coar-cgi-v11-00.txt> for the definition and usage of these variables.

The CGI Specification, and other associated documentation, should be consulted for general information on CGI script programming.

NATIVE LANGUAGE SUPPORT

If configured and installed with Native Language Support, Lynx will display status and other messages in your local language. See the file ABOUT_NLS in the source distribution, or at your local GNU site, for more information about internationalization.

The following environment variables may be used to alter default settings:

LANG

This variable, if set, will override the default message language. It is an ISO 639 two-letter code identifying the language. Language codes are NOT the same as the country codes given in ISO 3166.

LANGUAGE

This variable, if set, will override the default message language. This is a GNU extension that has higher priority for setting the message catalog than LANG or LC_ALL.

LC_ALL

and

LC_MESSAGES

These variables, if set, specify the notion of native language formatting style. They are POSIXly correct.

LINGUAS

This variable, if set prior to configuration, limits the installed languages to specific values. It is a space-separated list of two-letter codes. Currently, it is hard-coded to a wish list.

NLSPATH

This variable, if set, is used as the path prefix for message catalogs.

NOTES

This is the Lynx v2.8.2 Release

If you wish to contribute to the further development of Lynx, subscribe to our mailing list. Send email to <majordomo@sig.net> with "subscribe lynx-dev" as the only line in the body of your message.

Send bug reports, comments, suggestions to <lynx-dev@sig.net> after subscribing.

Unsubscribe by sending email to <majordomo@sig.net> with "unsubscribe lynx-dev" as the only line in the body of your message. Do not send the unsubscribe message to the lynx-dev list, itself.

SEE ALSO

catgets(3), curses(3), environ(7), execve(2), ftp(1), gettext(GNU), localeconv(3), ncurses(3), setlocale(3), slang(?), termcap(5), terminfo(5), wget(GNU)

Note that man page availability and section numbering is somewhat platform dependent, and may vary from the above references.

A section shown as (GNU), is intended to denote that the topic may be available via an info page, instead of a man page (i.e., try "info subject", rather than "man subject").

A section shown as (?) denotes that documentation on the topic exists, but is not part of an established documentation retrieval system (see the distribution files associated with the topic, or contact your System Administrator for further information).

ACKNOWLEDGMENTS

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. HYPERREZ was developed by Niel Larson of Think.com and served as the model for the early versions of Lynx. 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 the WWW community. Also a special thanks to Foteos Macrides who ported much of Lynx to VMS and did or organized most of its development since the departures of Lou Montulli and Garrett Blythe from the University of Kansas in the summer of 1994 through the release of v2.7.2, and to everyone on the net who has contributed to Lynx’s development either directly (through patches, comments or bug reports) or indirectly (through inspiration and development of other systems).

AUTHORS

Lou Montulli, Garrett Blythe, Craig Lavender, Michael Grobe, Charles Rezac
Academic Computing Services
University of Kansas
Lawrence, Kansas 66047

Foteos Macrides
Worcester Foundation for Biomedical Research
Shrewsbury, Massachusetts 01545