This chapter contains some example scripts that you can use. All of them come
contrib/lua/hooks.lua. I really recommend you to see it directly
instead of copying code out of this document. Also, not everything in there is
If you would like to contribute scripts, that would be great! Please send them to me at email@example.com. Cliff and I plan to start a script repository, provided we get some contributions. As for script ideas, you'll just have to be a little creative :-)
Also take a look at the
contrib/lua/ directory in the ELinks distribution.
Note that Peter and Cliff don't maintain the Lua support intensively anymore,
thus it would be probably nice to Cc me (firstname.lastname@example.org) if you want
to contribute some patch, so that I would be able to add it to the ELinks
There are some web sites that I visit often. Bookmarks are okay, but they are separate from the "Go to URL" dialog box, so I keep forgetting to use them. Also, when I visit a search engine home page, all I really want to do is enter a search term.
The following script allows me to type certain strings into the "Go to URL" dialog box, and it will convert them to the URL I actually want to visit. As a bonus, it allows me perform some searches on sites like Google without loading up the front page first.
The “URI rewriting” feature of ELinks handles many of the same tasks as the Lua hook shown here, and you can conveniently configure it via the option manager. It is not quite as versatile, though.
function match (prefix, url) return string.sub (url, 1, string.len (prefix)) == prefix end function strip (str) return string.gsub (str, "^%s*(.-)%s*$", "%1") end function plusify (str) return string.gsub (str, "%s", "+") end function goto_url_hook (url, current_url) -- Google search (e.g. ,gg unix browsers). if match (",gg", url) then url = plusify (strip (string.sub (url, 4))) return "http://www.google.com/search?q="..url.."&btnG=Google+Search" -- Freshmeat search. elseif match (",fm", url) then url = plusify (strip (string.sub (url, 4))) return "http://www.freshmeat.net/search/?q="..url -- Dictionary.com search (e.g. ,dict congenial). elseif match (",dict", url) then url = plusify (strip (string.sub (url, 6))) return "http://www.dictionary.com/cgi-bin/dict.pl?db=%2A&term="..url -- RPM search (e.g. ,rpm links). elseif match (",rpm", url) then url = plusify (strip (string.sub (url, 5))) return "http://www.rpmfind.net/linux/rpm2html/search.php?query=" ..url.."&submit=Search+..." -- Netcraft.com search (e.g. ,whatis www.google.com). elseif match (",whatis", url) then url = plusify (strip (string.sub (url, 8))) return "http://uptime.netcraft.com/up/graph/?host="..url -- LinuxToday home page. elseif match (",lt", url) then return "http://linuxtoday.com/" -- Weather forecast for Melbourne, Australia. elseif match (",forecast", url) then return "http://www.bom.gov.au/cgi-bin/wrap_fwo.pl?IDV10450.txt" -- Unmatched else return url end end
By adding an extra snippet of code to the previous example, we can make ELinks
expand pathnames such as
~user/zappo, like in the shell
and other Unix programs.
function goto_url_hook (url, current_url) . . -- Expand ~ to home directories. elseif match ("~", url) then if string.sub(url, 2, 2) == "/" then -- ~/foo return os.getenv ("HOME")..string.sub(url, 2) else -- ~foo/bar return "/home/"..string.sub(url, 2) end . .
Many web pages nowadays have columns to the left and right of the text, which are utterly useless. If you happen to be viewing the page in a 80x25 screen, the text you want to read ends up crammed into a tiny space in the centre. We use ELinks Lua support to manipulate the HTML before it reaches the parser.
This recipe is out of date for the web site.
Linux Today has two problems when viewed in ELinks: the useless columns on the left and the right and all the text appears in cyan. Here is a quick recipe to fix that:
-- Plain string.find (no metacharacters) function sstrfind (s, pattern) return string.find (s, pattern, 1, true) end function pre_format_html_hook (url, html) -- Strip the left and right columns from Linux Today pages -- and change the font colour to white. if sstrfind (url, "linuxtoday.com") then if sstrfind (url, "news_story") then html = string.gsub (html, '<TABLE CELLSPACING="0".-</TABLE>', '', 1) html = string.gsub (html, '<TR BGCOLOR="#FFF.-</TR></TABLE>', '', 1) else html = string.gsub (html, 'WIDTH="120">\n<TR.+</TABLE></TD>', '>', 1) end html = string.gsub (html, '<A HREF="http://www.internet.com.-</A>', '') html = string.gsub (html, "<IFRAME.-</IFRAME>", "") -- emphasis in text is lost return string.gsub (html, 'text="#002244"', 'text="#001133"', 1) end return nil end
This recipe is out of date for the web site.
Here is a simpler example, for http://www.linuxgames.com/.
function pre_format_html_hook (url, html) . . elseif string.find (url, "linuxgames.com", 1, true) then return string.gsub (html, "<CENTER>.-</center>", "", 1) . .
ELinks already supports gzipped files natively.
Sometimes documents come gzipped in order to save space, but then you need to uncompress them to read them with ELinks. Here is a recipe to handle gzipped files on a Unix system.
This recipe opens a temporary file insecurely.
function pre_format_html_hook (url, html) . . -- Handle gzip'd files within reasonable size. if string.find (url, "%.gz$") and string.len (html) < 65536 then local name = tmpname () local file = io.open (name, "wb") file:write (html) file:close () html = pipe_read ("(gzip -dc "..name.." || cat "..name..") 2>/dev/null") os.remove (name) return html end . .
Printing a web page with ELinks usually involves quite a few steps: Save the current document onto disk. Run it through ELinks on the command-line (so it fits into 80 columns) to generate a plain text version. Remove the 80th column from the text version, as it will make printers wrap down to the next line. Finally, run the processed file through `lpr', then delete it.
The following functions allow you to print web pages directly from ELinks,
lpr' or `enscript'. Type `lpr() or
enscript() in the Lua Console to
run them. (In the
hooks.lua, I have also made it so you can just type
io.popen function is not available on all platforms.
function pipe_formatted_to (program) local lp, errmsg = io.popen (program, "w") if lp == nil then error (errmsg) else lp:write (current_document_formatted (79)) lp:close () end end -- Send the current document to `lpr'. function lpr () pipe_formatted_to ("lpr") end -- Send the current document to `enscript'. function enscript () pipe_formatted_to ("enscript -fCourier8") end
If you come across a brain-dead web page that is totally unreadable with ELinks, you'd probably want to open it with a graphical browser. The following function opens the current document in Netscape.
You can also use the built-in “URI passing” feature for this.
-- When starting Netscape: Set to `nil' if you do not want -- to open a new window for each document. netscape_new_window = 1 -- Open current document in Netscape. function netscape () local new = netscape_new_window and ",new_window" or "" execute ("( netscape -remote 'openURL("..current_url ()..new..")'" .." || netscape '"..current_url ().."' ) 2>/dev/null &") end
Many people would like to have a bookmark system with categories (note that ELinks already supports that, marketing name Hierarchical bookmarks), and also to be able to view them and search for them in an HTML page. I have written an alternative bookmark system (for ELinks), which some people may like better than the standard bookmark system.