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9 File : $Source: /cvsroot/ijbswa/current/doc/source/faq.sgml,v $
12 This file belongs into
13 ijbswa.sourceforge.net:/home/groups/i/ij/ijbswa/htdocs/
15 $Id: faq.sgml,v 1.37 2002/04/01 16:24:07 hal9 Exp $
17 Written by and Copyright (C) 2001 the SourceForge
18 Privoxy team. http://www.privoxy.org/
20 Based on the Internet Junkbuster originally written
21 by and Copyright (C) 1997 Anonymous Coders and
22 Junkbusters Corporation. http://www.junkbusters.com
24 =============================================================
25 IMPORTANT: READ: This document does not use automatic section
26 numbering. It is turned off by GNUmakefile to keep the Table
27 of contents from being so messy. Sections will need to be
28 manually numbered as a consequence.
29 =============================================================
36 <title>Privoxy Frequently Asked Questions</title>
38 <pubdate>$Id: faq.sgml,v 1.37 2002/04/01 16:24:07 hal9 Exp $</pubdate>
43 <orgname>By: Privoxy Developers</orgname>
52 This is here to keep vim syntax file from breaking :/
53 If I knew enough to fix it, I would.
54 PLEASE DO NOT REMOVE! HB: hal@foobox.net
59 This FAQ gives users and developers alike answers to frequently asked
60 questions about <ulink url="http://www.privoxy.org">Privoxy</ulink>.
64 Include privoxy.sgml boilerplate:
69 You can find the latest version of the document at <ulink
70 url="http://www.privoxy.org/faq/">http://www.privoxy.org/faq/</ulink>.
71 Please see the Contact section in the <ulink
72 url="http://www.privoxy.org/user-manual/contact.html">user-manual</ulink> if
73 you want to contact the developers.
77 <!-- Feel free to send a note to the developers at <email>ijbswa-developers@lists.sourceforge.net</email>. -->
83 <!-- ~~~~~ New section ~~~~~ -->
86 <!-- dummy section to force TOC on page by itself -->
87 <!-- DO NOT REMOVE! please ;) -->
91 <!-- ~~~~~ New section ~~~~~ -->
93 <sect1 id="general"><title>1. General Information</title>
95 <sect2 id="newjb"><title>What is this new version of <application>Privoxy</application>?</title>
97 The original <application>Internet Junkbuster</application> (tm) is a
98 copyrighted product of <ulink url="http://www.junkbusters.com">Junkbusters
99 Corporation</ulink>. Development of this effort stopped some time ago as of
100 version 2.0.2. Stefan Waldherr started the ijbswa project on <ulink
101 url="http://sourceforge.net/projects/ijbswa/">Sourceforge</ulink> to rekindle
102 development. Other developers subsequently joined with Stefan, and have
103 since added many new features, refinements and enhancements. The result
104 of this effort is <application>Privoxy</application>.
107 <application>Privoxy</application> started with the
108 <application>Junkbuster 2.0.2</application> code base, but has advanced
109 significantly at this point.
112 Please see the <ulink
113 url="../user-manual/copyright.html#HISTORY">user-manual</ulink> for more
114 information on the history of <application>Junkbuster</application> and
115 <application>Privoxy</application>.
122 <title id="whyprivoxy">Why <quote>Privoxy</quote>? Why a name change at all?</title>
124 <application>Privoxy</application> is the
125 <quote><emphasis>Privacy Enhancing Proxy</emphasis></quote>.
128 There are possible legal complications from the continued use of the
129 <application>Junkbuster</application> name, which is a trademark of
130 <ulink url="http://junkbusters.com">Junkbusters Corporation</ulink>.
131 (There are, however, no objections from Junkbusters Corporation to the
132 <application>Privoxy</application> project itself, and they, in fact, still
133 share our ideals and goals.)
137 The developers also believed that there so many changes from the original
138 code, that it was time to make a clean break from the past and make
139 a name in their own right, especially now with the pending release of
146 <sect2 id="differs"><title>How does <application>Privoxy</application> differ
147 from the old <application>Junkbuster?</application></title>
149 <application>Privoxy</application> picks up where
150 <application>Junkbuster</application> left off. All the old features remain.
151 The new <application>Privoxy</application> still blocks ads and banners,
152 still manages cookies, and still helps protect your privacy. But, these are
153 all enhanced, and many new features have been added, all in the same vein.
156 The configuration has changed significantly as well. This is something that
157 users will notice right off the bat. The <quote>blocklist</quote> file does
158 not exist any more. This is replaced by <quote>actions</quote> files, such
159 as <filename>default.actions</filename>. This is where most of the per site
160 configuration is now.
165 <sect2 id="features"><title>What are some of the new features?</title>
167 Include newfeatures.sgml
173 <sect2 id="proxymoron"><title>What is a <quote>proxy</quote>? How does
174 <application>Privoxy</application> work? </title>
176 When you connect to a web site with <application>Privoxy</application>,
177 you are really connecting to your locally running version of
178 <application>Privoxy</application>. <application>Privoxy</application>
179 intercepts your requests for the web page, and relays that to the
180 <quote>real</quote> web site. The web site sends the HTTP data stream
181 back to <application>Privoxy</application>, where
182 <application>Privoxy</application> can work its magic before it
183 relays this data back to your web browser.
187 Since <application>Privoxy</application> sits between you and the
188 WWW, it is in a position to intercept and completely manage all web traffic and
189 HTTP content before it gets to your browser.
190 <application>Privoxy</application> uses various programming methods to do
191 this, all of which is under your control via the various configuration
196 There are many kinds of proxies. <application>Privoxy</application> best
197 fits the <quote>filtering proxy</quote> category.
204 <title id="knows">How does <application>Privoxy</application> know what is
205 an ad, and what is not?</title>
207 <application>Privoxy</application> processes all the raw content of every
208 web page. So it reads everything on each page. It then compares this to the
209 rules as set up in the configuration files, and looks for any matches to
210 these rules. <application>Privoxy</application> makes heavy use of
211 <quote>regular expressions</quote>. (If you are not familiar with regular
212 expressions, it is explained briefly in <ulink
213 url="../user-manual/appendix.html">the user manual</ulink>.) Regular
214 expressions facilitate matching of one text string against another, using
215 wildcards to build complex patterns. So <application>Privoxy</application>
216 will typically look for URLs and other content that match certain key words
217 and expressions as defined in the configuration files. For instance a URL
218 that contains <quote>/banners</quote>, has a high probability of containing
219 ad banners, and thus would be a prime candidate to have a matching rule.
222 So <application>Privoxy</application> will look for these kinds of obvious
223 looking culprits. And also, will use lists of known organizations that
224 specialize in ads. Again, using complex patterns to match as many potential
225 combinations as possible since there tend to be many, many variations used by
226 advertisers, and new ones are being introduced all the time.
231 <title id="mistakes">Can <application>Privoxy</application> make mistakes?
232 This does not sound very scientific.</title>
234 Actually, it's a black art ;-) And yes, it is always possible to have a broad rule
235 accidentally block something by mistake. There is a good chance you may run
236 into such a situation at some point. It is tricky writing rules to cover
237 every conceivable possibility, and not occasionally get false positives.
241 But this should not be a big concern since the
242 <application>Privoxy</application> configuration is very flexible, and
243 includes tools to help identify these types of situations so they can be
244 addressed as needed, allowing you to customize your installation.
245 (<link linkend="badsite">See the appendix below</link>.)
251 <sect2 id="browsers2"><title>My browser does the same things as
252 <application>Privoxy</application>. Why should I use
253 <application>Privoxy</application> at all?</title>
255 Modern browsers do indeed have <emphasis>some</emphasis> of the same
256 functionality as <application>Privoxy</application>. Maybe this is
257 adequate for you. But <application>Privoxy</application> is much more
258 versatile and powerful, and can do a number of things that browsers just can't.
261 In addition, a proxy is good choice if you use multiple browsers, or
262 have a LAN with multiple computers. This way all the configuration
263 is in one place, and you don't have to maintain a similar configuration
264 for possibly many browsers.
271 <sect2 id="license"><title>Is there is a license or fee? What about a
272 warranty? Registration?</title>
274 <application>Privoxy</application> is licensed under the
275 GNU General Public License (GPL). It is free to use, copy,
276 modify or distribute as you wish under the terms of this license.
278 <ulink url="../user-manual/copyright.html#HISTORY">user-manual</ulink> for
279 more information on the license and copyright.
283 There is no warranty of any kind, expressed, implied or otherwise. That is
284 something that would cost real money ;-) There is no registration either.
285 <application>Privoxy</application> really is <emphasis>free</emphasis>
292 <sect2 id="jointeam"><title>I would like to help you, what do I do?</title>
294 <sect3 id="jointeam-money"><title>Money Money Money</title>
296 We, of course, welcome donations and use the money for domain registering,
297 regular world-wide get-togethers (hahaha). Anyway, we'll soon describe the
298 process how to donate money to the team.
302 <sect3 id="jointeam-work"><title>You want to work with us?</title>
304 Well, helping the team is always a good idea. We welcome new developers,
305 RPM gurus or documentation makers. Simply get an account on sourceforge.net
306 and mail your id to the developer mailing list. Then read the
307 section Quickstart in the <ulink url="http://privoxy.org/developer-manual/quickstart.html">
308 Developer's Manual</ulink>.
311 Once we have added you to the team, you'll have write access to the CVS
312 repository, and together we'll find a suitable task for you.
321 <!-- ~~~~~ New section ~~~~~ -->
323 <sect1 id="installation"><title>2. Installation</title>
325 <sect2 id="whichbrowsers">
326 <title>Which browsers are supported by <application>Privoxy</application>?</title>
328 Any browser that can be configured to use a <quote>proxy</quote>, which
329 should be virtually all browsers. Direct browser support is not necessary
330 since <application>Privoxy</application> runs as a separate application and
331 just exchanges standard HTML data with your browser, just like a web server
337 <title>Which operating systems are supported?</title>
339 Include supported.sgml here:
344 <sect2 id="newinstall"><title>Can I install
345 <application>Privoxy</application> over <application>Junkbuster</application>?</title>
347 We recommend you uninstall <application>Junkbuster</application>
348 first to minimize conflicts and confusion. You may want to
349 save your old configuration files for future reference. The configuration
350 is substantially changed.
354 url="../user-manual/index.html">user-manual</ulink> for
355 platform specific installation instructions. [FIXME: This is meant for after
356 the name change for 3.0!]
359 Note: Some installers may automatically uninstall
360 <application>Junkbuster</application>, if present!
366 <title id="firststep">I just installed <application>Privoxy</application>. Is there anything
367 special I have to do now?</title>
370 All browsers must be told to use <application>Privoxy</application>
371 as a proxy by specifying the correct proxy address and port number
372 in the appropriate configuration area for the browser. See below.
373 Also, you should flush your browser's memory and disk cache to get rid of any
381 <sect2 id="localhost"><title>What is the proxy address of <application>Privoxy</application>?</title>
383 If you set up the <application>Privoxy</application> to run on
384 the computer you browse from (rather than your ISP's server or some
385 networked computer on a LAN), the proxy will be on <quote>localhost</quote>
386 (which is the special name used by every computer on the Internet to refer
387 to itself) and the port will be 8118 (unless you have <application>Privoxy</application> to run on a different port with the
388 <emphasis>listen-address</emphasis> config option).
391 When configuring your browser's proxy settings you typically enter
392 the word <quote>localhost</quote> in the boxes next to <quote>HTTP</quote>
393 and <quote>Secure</quote> (HTTPS) and then the number <quote>8118</quote>
394 for <quote>port</quote>. This tells your browser to send all web
395 requests to <application>Privoxy</application> instead of directly to the
399 <application>Privoxy</application> can also be used to proxy for
400 a Local Area Network. In this case, your would enter either the IP
401 address of the LAN host where <application>Privoxy</application>
402 is running, or the equivalent hostname. Port assignment would be
406 <application>Privoxy</application> does not currently handle
407 protocols such as FTP, SMTP, IM, IRC, ICQ, or other Internet
413 <title id="nothing">I just installed <application>Privoxy</application>, and nothing is happening.
414 All the ads are there. What's wrong?</title>
417 Did you configure your browser to use <application>Privoxy</application>
418 as a proxy? It does not sound like it. See above. You might also try flushing
419 the browser's caches to force a full re-reading of pages. You can verify
420 that <application>Privoxy</application> is running, and your browser
421 is correctly configured by entering the special URL:
422 <ulink url="http://p.p/">http://p.p/</ulink>. This should give you
423 a banner that says <quote>This is Privoxy</quote> and
424 access to <application>Privoxy's</application> internal configuration.
425 If you see this, then you are good to go. If not, the browser or
426 <application>Privoxy</application> are not set up correctly.
435 <!-- ~~~~~ New section ~~~~~ -->
437 <sect1 id="configuration"><title>3. Configuration</title>
439 <sect2 id="newconfig"><title>Can I use my old config files?</title>
441 There are major changes to <application>Junkbuster</application>,
442 <application>Privoxy</application>, configuration from version 2.0.x to
443 2.9.x and later. Most of the older files will not work at all. This is
444 especially true of <filename>blocklist</filename>. If this is the case, you
445 will need to re-enter your old data into the new configuration structure.
446 This is probably also a good recommendation even if upgrading from 2.9.x to
447 3.x since there were many minor changes along the way.
452 <title id="actionsfile">What is an <quote>actions</quote> file?</title>
455 <quote>actions</quote> files are where various actions that
456 <application>Privoxy</application> might take, are configured.
457 Typically, you would define a set of default actions that apply
458 to all URLs, then add exceptions to these defaults.
462 Actions can be defined on a per site basis, or for groups of sites. Actions
463 can also be grouped together and then applied to one or more sites. There
464 are many possible actions that might apply to any given site. As an example,
465 if we are blocking cookies as one of our default
466 <application>actions</application>, but need to accept cookies from a given
467 site, we would define this in our <quote>actions</quote> file.
472 <application>Privoxy</application> comes with several default
473 <application>actions</application> files, with varying degrees
474 of filtering and blocking, as starting points for your own
475 configuration (see below).
480 <sect2 id="actionss">
481 <title>The <quote>actions</quote>concept confuses me. Please list
482 some of these <quote>actions</quote>.</title>
484 These are all explained in the
485 <ulink url="../user-manual/configuration.html#ACTIONSFILE">user-manual</ulink>.
486 Please refer to that.
492 <title id="actconfig">How are actions files configured? What is the easiest
493 way to do this?</title>
496 The easiest way to do this, is to access <application>Privoxy</application>
497 with your web browser at <ulink url="http://p.p/">http://p.p/</ulink>,
499 "<ulink url="http://config.privoxy.org">Edit the actions list</ulink>"
500 from the selection list. You can also do this by editing the appropriate
501 file with a text editor.
507 url="../user-manual/configuration.html#ACTIONSFILE">user-manual</ulink> for a
508 detailed explanation of these and other configuration files, and their
509 various options and syntax.
515 FIXME: Commenting these out until we have some data there. HB 03/17/02.
517 <sect2 id="yahoo"><title>How can I make my Yahoo account work?</title>
523 <sect2 id="hotmail"> <title>How can I make my Hotmail account work?</title>
529 <sect2 id="gmx"> <title>How can I make my GMX account work?</title>
536 <sect2 id="configfiles"> <title>What are the differences between
537 intermediate.action, basic.action, etc.?</title>
539 Configuring <application>Privoxy</application> is not easy. To help you get
540 started, we provide you with three different default configurations. The
541 following table shows you, which features are enabled in each configuration.
544 <table frame=all><title>Default Configurations</title>
545 <tgroup cols=5 align=left colsep=1 rowsep=1>
553 <entry>Feature</entry>
554 <entry>default.action</entry>
555 <entry>basic.action</entry>
556 <entry>intermediate.action</entry>
557 <entry>advanced.action</entry>
563 <!-- <entry>f1</entry> -->
564 <!-- <entry>f2</entry> -->
565 <!-- <entry>f3</entry> -->
566 <!-- <entry>f4</entry> -->
567 <!-- <entry>f5</entry> -->
574 <entry>ad-filtering</entry>
582 <entry>blank image</entry>
590 <entry>de-animate GIFs</entry>
598 <entry>referer forging</entry>
606 <entry>jon's +no-cookies-keep (i.e. session cookies only)</entry>
614 <entry>no-popup windows</entry>
622 <entry>fast redirects</entry>
630 <entry>hide-referrer</entry>
638 <entry>hide-useragent</entry>
646 <entry>content-modification</entry>
654 <entry>feature-x</entry>
662 <entry>feature-y</entry>
670 <entry>feature-z</entry>
683 <sect2 id="browseconfig"> <title>Why can I change the configuration with a
684 browser? Does that not raise security issues?</title>
686 What I don't understand, is how I can browser edit the config file as a
687 regular user, while the whole /etc/privoxy hierarchy belongs to the user
688 "privoxy", with only 644 perms.
691 When you use the browser-based editor, <application>Privoxy</application>
692 itself is writing to the config files. Because
693 <application>Privoxy</application> is running as the user "privoxy", it can
694 update the config files.
697 If you don't like this, setting "enable-edit-actions 0" in the config file
698 will disable the browser-based editor. If you're that paranoid, you should
699 also consider setting "enable-remote-toggle 0" to prevent browser-based
700 enabling/disabling of <application>Privoxy</application>.
703 Note that normally only local users can connect to <application>Privoxy</application>, so this is not
704 (normally) a security problem.
710 <title id="filterfile">What is <quote>default.filter</quote>?</title>
712 The <quote>default.filter</quote> file is used to <quote>filter</quote> any
713 web page content. By <quote>filtering</quote> we mean it can modify, remove,
714 or change <emphasis>anything</emphasis> on the page, including HTML tags, and
715 JavaScript. Regular expressions are used to accomplish this, and operate
716 on a line by line basis. This is potentially a very powerful feature, but
717 requires some expertise.
721 If you are familiar with regular expressions, and HTML, you can look at
722 the provided <filename>default.filter</filename> with a text editor and see
723 some of things it can be used for.
727 Presently, there is no GUI editor option for this part of the configuration,
728 but you can disable/enable various sections of the included default
729 file with the <quote>Actions List Editor</quote> from your browser.
735 <title id="lanconfig">How can I set up <application>Privoxy</application> to act as a proxy for my
738 By default, <application>Privoxy</application> only responds to requests
739 from localhost. To have it act as a server for a network, this needs to be
740 changed in the main config file where the <application>Privoxy</application>
741 configuration is located. In that file is a <quote>listen-address</quote>
742 option. It may be commented out with a <quote>#</quote> symbol. Make sure
743 it is uncommented, and assign it the address of the LAN gateway interface,
744 and port number to use:
749 listen-address 192.168.1.1:8118
754 Save the file, and restart <application>Privoxy</application>. Configure
755 all browsers on the network then to use this address and port number.
762 <title id="noseeum">Instead of ads, now I get a checkerboard pattern. I don't want to see anything.</title>
764 This is a configuration option for images that
765 <application>Privoxy</application> is stopping. You have the choice <!-- of
766 the --> <!-- <application>Privoxy</application> logo, --> of a checkerboard
767 pattern, a transparent 1x1 GIF image (aka <quote>blank</quote>), or a custom
768 URL of your choice. Note that to fit this category, the URL must match both
769 the <quote>+image</quote> and <quote>+block</quote> actions.
773 If you want to see nothing, then change the <quote>+image-blocker</quote>
774 action to <quote>+image-blocker{blank}</quote>. This can be done from the
775 <quote>Edit Actions List</quote> selection at <ulink
776 url="http://p.p/">http://p.p/</ulink>. Or by hand editing the appropriate
777 actions file. This will only effect what is defined as <quote>images</quote>
778 though. Also, some URLs that generate the bright red <quote>Blocked</quote>
779 banner, can be moved to the <quote>+image-blocker</quote> section for the
780 same reason, but there are some limits and risks to this (see below).
787 <title id="whyseeum">Why would anybody want to see a checkerboard pattern?</title>
789 This can be helpful for troubleshooting problems. It might also be good
790 for anyone new to <application>Privoxy</application> so that they can
791 see if their favorite pages are displaying correctly, and
792 <application>Privoxy</application> is not inadvertently removing something
799 <title id="blockedisugly">I see large red banners on some pages that say
800 <quote>Blocked</quote>. Why and how do I get rid of this?</title>
802 These are URLs that match something in one of
803 <application>Privoxy's</application> block actions (+block). It is meant
804 to be a warning so that you know something has been blocked and an easy way
805 for you to see why. These are handled differently than what has been defined
806 explicitly as <quote>images</quote> (e.g. ad banners). Depending on the
807 URL itself, it is sometimes hard for <application>Privoxy</application> to
808 really know whether there is indeed an ad image there or not. And there are
809 limitations as to what <application>Privoxy</application> can do to
810 <quote>fool</quote> the browser.
814 For instance, if the ad is in a frame, then it is embedded in the separate
815 HTML page used for the frame. In this case, you cannot just substitute an
816 aribitray image (like we would for a <quote>blank</quote> image), for an HTML
817 page. The browser is expecting an HTML page, and that is what it must have
818 for frames. So this situation can be a little trickier to deal with, and
819 <application>Privoxy</application> will use the <quote>Blocked</quote> page.
823 If you want these to be treated as if they were images, so that they can be
824 made invisible, you can try moving the offending URL from the
825 <quote>+block</quote> section to the <quote>+imageblock</quote> section of
826 your actions file. Just be forewarned, if any URL is made
827 <quote>invisible</quote>, you may not have any inkling that something has
828 been removed from that page, or why. If this approach does not work, then you are
829 probably dealing with a frame (or <quote>ilayer</quote>), and the only thing
830 that can go there is an HTML page of some sort.
833 To deal with this situation, you could modify the
834 <quote><filename>block</filename></quote> HTML template that is used by
835 <application>Privoxy</application> to display this, and make it something
836 more to your liking. Currently, there is no configuration option for this.
837 You will have to modify, or create your own page, and use this to replace
838 <filename>templates/blocked</filename>, which is what
839 <application>Privoxy</application> uses to display the <quote>Blocked</quote>
843 Another way to deal with this is find why and where
844 <application>Privoxy</application> is blocking the frame, and
845 diable this. Then let the <quote>+image-blocker</quote> action
846 handle the ad that is embedded in the frame's HTML page.
851 <sect2 id="alliseeisred">
852 <title>I cannot see all of the <quote>Blocked</quote> page banner. All I
853 see is a bright red square.</title>
855 There is not enough space to fit the entire page. Try right clicking on the
856 visible, red portion, and select <quote>Show Frame</quote>, or equivalent.
857 This will usually allow you to see the entire Privoxy <quote>Blocked</quote>
858 page, and from there you can see just what is being blocked, and why.
862 <sect2 id="otherproxy">
863 <title>How can I make <application>Privoxy</application> work with other
864 proxies like <application>Squid</application>?</title>
866 This can be done. See the <ulink
867 url="../user-manual/configuration.html#FORWARDING">user manual</ulink>,
868 which describes how to do this.
876 <!-- ~~~~~ New section ~~~~~ -->
878 <sect1 id="misc"><title>4. Miscellaneous</title>
881 <title id="slowsme">How much does <application>Privoxy</application> slow my browsing down? This
882 has to add extra time to browsing.</title>
884 It should not slow you down any in real terms, and may actually help
885 speed things up since ads, banners and other junk are not being displayed.
886 The actual processing time required by <application>Privoxy</application>
887 itself for each page, is relatively small in the overall scheme of things,
888 and happens very quickly. This is typically more than offset by time saved
889 not downloading and rendering ad images.
893 <quote>Filtering</quote> via the <filename>filterfile</filename>
894 mechanism may cause a perceived slowdown, since the entire page is buffered
895 before displaying. See below.
902 <sect2 id="loadingtimes"><title>I noticed considerable
903 delays in page requests compared to the old Junkbuster. What's wrong?</title>
905 Using the default filtering configuration, I noticed considerable delays in
906 page requests compared to the old Junkbuster. Loading pages with large contents
907 seemed to take forever, then suddenly delivering all the content at once.
910 The whole content must be loaded in order to filter, and nothing is is
911 sent to the browser during this time. The loading time does not really
912 change in real numbers, but the feeling is different, because most
913 browsers are able to start rendering incomplete content, giving the
914 user a feeling of "it works".
917 To modify the content of a page (i.e. make frames resizeable again, etc.) and
918 not just replace ads, <application>Privoxy</application> needs to download the
919 entire page first, do its content magic and then send the page to the browser.
924 <sect2 id="configurl"><title>What is the "http://p.p/"?</title>
926 Since <application>Privoxy</application> sits between your web browser and the Internet, it can be
927 programmed to handle certain pages specially.
931 With recent versions of <application>Privoxy</application> (version 2.9.x), you can get some
932 information about <application>Privoxy</application> and change some settings by going to
933 <ulink url="http://p.p/">http://p.p/</ulink> or, equivalently, <ulink url="http://config.privoxy.org/">http://config.privoxy.org/</ulink>
934 (Note that p.p is far easier to type but may not work in some
935 configurations. With the name change to <application>Privoxy</application>,
936 this is changed from the previous http://i.j.b/ or earlier 2.9.x versions).
940 These pages are <emphasis>not</emphasis> forwarded to a server on the Internet
941 - instead they are handled by a special web server which is built in to
942 <application>Privoxy</application>.
946 If you are not running <application>Privoxy</application>, then <ulink
947 url="http://p.p/">http://p.p/</ulink> will fail, and <ulink
948 url="http://config.privoxy.org/">http://config.privoxy.org/</ulink> will
949 return a web page telling you you're not running
950 <application>Privoxy</application>.
954 If you have version 2.0.2, then the equivalent is
955 http://example.com/show-proxy-args (but you get far less information, and you
956 should really consider upgrading to 2.9.x).
961 FIXME: commented out until we have data. HB 03/18/02.
963 <sect2 id="badfiledesc"><title>I get the message 'Bad File Descriptor', why?</title>
969 <sect2 id="proxy-chaining"><title>How do I chain <application>Privoxy</application> with other proxies
970 (e.g. squid)?</title>
977 <sect2 id="blocklist"><title>Do you still maintain the blocklists?</title>
979 No. The format of the blocklists has changed significantly in the versions
980 2.9.x. Once we have released the new stable version, v3.0, there will
981 again be blocklists that you can update automatically.
985 <sect2 id="newads"><title>How can I submit new ads?</title>
987 As of now, please discontinue to submit new ad blocking infos. Once we
988 have released the new version, there will again be a form on the website,
989 which you can use to contribute new ads.
993 <sect2 id="ip"><title>How can I hide my IP address?</title>
995 You cannot hide your IP address with <application>Privoxy</application> or any other software, since
996 the server needs to know your IP address to send the answer to you.
999 Fortunately there are many publicly usable anonymous proxies out there, which
1000 solve the problem by providing a further level of indirection between you and
1001 the web server, shared by many people and thus letting your requests "drown"
1002 in white noise of unrelated requests as far as user tracking is concerned.
1005 Most of them will, however, log your IP address and make it available to the
1006 authorities in case you abuse that anonymity for criminal purposes. In fact
1007 you can't even rule out that some of them only exist to *collect* information
1008 on (those suspicious) people with a more than average preference for privacy.
1011 You can find a list of anonymous public proxies at <ulink
1012 url="http://www.multiproxy.org/anon_list.htm">multiproxy.org</ulink> and many
1013 more through Google.
1017 <!-- <sect2 id="image"><title>What is the imagefile (simage.ini, etc.) for?</title> -->
1019 <!-- Anytime <application>Privoxy</application> determines (with the help of the blocklist) that a URL -->
1020 <!-- contains an advertisement, it has to decide whether this advertisement is an -->
1021 <!-- image or not. <application>Privoxy</application> uses the imagefile for that purpose. -->
1026 <title id="anonforsure">Can <application>Privoxy</application> guarantee I am anonymous?</title>
1028 No. Your chances of remaining anonymous are greatly improved, but unless you
1029 are an expert on Internet security it would be safest to assume that
1030 everything you do on the Web can be traced back to you.
1033 <application>Privoxy</application> can remove various information about you,
1034 and allows <emphasis>you</emphasis> more freedom to decide which sites
1035 you can trust. But it's still possible that web sites can find out who you
1036 are. Here's one way this can happen.
1039 A few browsers disclose the user's email address in certain situations, such
1040 as when transferring a file by FTP. <application>Privoxy</application>
1041 does not filter FTP. If you need this feature, or are concerned about the
1042 mail handler of your browser disclosing your email address, you might
1043 consider products such as <application>NSClean</application>.
1046 Browsers available only as binaries could use non-standard headers to give
1047 out any information they can have access to: see the manufacturer's license
1048 agreement. It's impossible to anticipate and prevent every breach of privacy
1049 that might occur. The professionally paranoid prefer browsers available as
1050 source code, because anticipating their behavior is easier. Trust the source,
1057 <title id="sitebreak">Might some things break because header information is
1058 being altered?</title>
1061 Definitely. More and more sites use HTTP header content to decide what to
1062 display and how to display it. There is many ways that this can be handled,
1063 so having hard and fast rules, is tricky.
1067 <quote>USER AGENT</quote> in particular is often used in this way to identify
1068 the browser, and adjust content accordingly. Changing this now is not
1069 recommended, since so many sites do look for this. You may get undesirable
1070 results by changing this.
1074 For instance, different browsers use different encodings of Russian and Czech
1075 characters, certain web servers convert pages on-the-fly according to the
1076 User Agent header. Giving a <quote>User Agent</quote> with the wrong
1077 operating system or browser manufacturer causes some sites in these languages
1078 to be garbled; Surfers to Eastern European sites should change it to
1079 something closer. And then some page access counters work by looking at the
1080 <quote>REFERER</quote> header; they may fail or break if unavailable. The
1081 weather maps of Intellicast have been blocked by their server when no
1082 <quote>REFERER</quote> or cookie is provided, is another example. There are
1083 many, many other ways things can go wrong when trying to fool a web server.
1087 If you have problems with a site, you will have to adjust your configuration
1088 accordingly. Cookies are probably the most likely adjustment that may
1089 be required, but by no means the only one.
1097 <title id="caching">Can <application>Privoxy</application> act as a <quote>caching</quote> proxy to
1098 speed up web browsing?</title>
1100 No, it does not have this ability at all. You want something like
1101 <ulink url="http://www.squid-cache.org/">Squid</ulink> for this. And, yes,
1102 before you ask, <application>Privoxy</application> can co-exist
1103 with other kinds of proxies like <application>Squid</application>.
1108 <title id="firewall">What about as a firewall? Can <application>Privoxy</application> protect me?</title>
1110 Not in the way you mean, or in the way a true firewall can, or a proxy that
1111 has this specific capability. <application>Privoxy</application> can help
1112 protect your privacy, but not really protect you from intrusion attempts.
1118 <title id="logo">The <application>Privoxy</application> logo that replaces ads is very blocky
1119 and ugly looking. Can't a better font be used?</title>
1122 This is not a font problem. The logo is an image that is created by
1123 <application>Privoxy</application> on the fly. So as to not waste
1124 memory, the image is rather small. The blockiness comes when the
1125 image is scaled to fill a largish area. There is not much to be done
1126 about this, other than to use one of the other
1127 <quote>imageblock</quote> directives: <emphasis>pattern</emphasis>,
1128 <emphasis>blank</emphasis>, or a URL of your choosing.
1131 Given the above problem, we have decided to remove the logo option entirely
1138 <title id="wasted">I have large empty spaces now where ads used to be.
1141 It would be easy enough to just eliminate this space altogether, rather than
1142 fill it with blank space. But, this would create problems with many pages
1143 that use the overall size of the ad to help organize the page layout and
1144 position the various components of the page where they were intended to be.
1145 It is best left this way.
1151 <title id="ssl">How can <application>Privoxy</application> filter Secure (HTTPS) URLs?</title>
1153 This is a limitation since HTTPS transactions are encrypted SSL sessions
1154 between your browser and the secure site, and are meant to be reliably
1155 <emphasis>secure</emphasis> and private. This means that all cookies and HTTP
1156 header information are also encrypted from the time they leave your browser,
1157 to the site, and vice versa. <application>Privoxy</application> does not
1158 try to unencrypt this information, so it just passes through as is.
1159 <application>Privoxy</application> can still catch images and ads that
1160 are embedded in the SSL stream though.
1167 <title id="secure"><application>Privoxy</application> runs as a <quote>server</quote>. How
1168 secure is it? Do I need to take any special precautions?</title>
1170 There are no known exploits that might effect
1171 <application>Privoxy</application>. On Unix-like systems,
1172 <application>Privoxy</application> can run as a non-privileged
1173 user, which is how we recommend it be run. Also, by default
1174 <application>Privoxy</application> only listens to requests
1175 from <quote>localhost</quote>. The server aspect of
1176 <application>Privoxy</application> is not itself directly exposed to the
1177 Internet in this configuration. If you want to have
1178 <application>Privoxy</application> serve as a LAN proxy, this will have to
1179 be opened up to allow for LAN requests. In this case, we'd recommend
1180 you specify only the LAN gateway address, e.g. 192.168.1.1, in the main
1181 <application>Privoxy</application> config file. All LAN hosts can then use
1182 this as their proxy address in the browser proxy configuration. In this way,
1183 <application>Privoxy</application> will not listen on any external ports.
1184 Of course, a firewall is always good too. Better safe than sorry.
1189 <sect2 id="turnoff">
1190 <title>How can I temporarily disable <application>Privoxy</application>?</title>
1192 The easiest way is to access <application>Privoxy</application> with your
1193 browser by using the special URL: <ulink url="http://p.p/">http://p.p/</ulink>
1194 and select "Toggle Privoxy on or off" from that page.
1199 <sect2 id="seealso">
1200 <title>Where can I find more information about <application>Privoxy</application>
1201 and related issues?</title>
1204 Include seealso.sgml
1212 <ulink url="../user-manual/seealso.html">user-manual</ulink> for
1221 <!-- ~~~~~ New section ~~~~~ -->
1223 <sect1 id="trouble">
1224 <title>5. Troubleshooting</title>
1227 <title id="refused">I just upgraded and am getting <quote>connection refused</quote>
1228 with every web page?</title>
1230 Either <application>Privoxy</application> is not running, or your
1231 browser is configured for a different port than what
1232 <application>Privoxy</application> is using.
1236 The old <application>Privoxy</application> (and also
1237 <application>Junkbuster</application>) used port 8000 by
1238 default. This has been changed to port 8118 now, due to a conflict
1239 with NAS (Network Audio Service), which uses port 8000. If you haven't,
1240 you need to change your browser to the new port number, or alternately
1241 change <application>Privoxy's</application> <quote>listen-address</quote>
1242 setting in the <filename>config</filename> file used to start
1243 <application>Privoxy</application>.
1249 <title id="flushit">I just added a new rule, but the steenkin ad is
1250 still getting through. How?</title>
1252 If the ad had been displayed before you added its URL, it will probably be
1253 held in the browser's cache for some time, so it will be displayed without
1254 the need for any request to the server, and <application>Privoxy</application>
1255 will not be in the picture. The best thing to do is try flushing the browser's
1256 caches. And then try again.
1260 If this doesn't help, you probably have an error in the rule you
1261 applied. Try pasting the full URL of the offending ad into <ulink
1262 url="http://config.privoxy.org/show-url-info">http://config.privoxy.org/show-url-info</ulink>
1263 and see if any actions match your new rule.
1269 <title id="badsite">One of my favorite sites does not work with <application>Privoxy</application>.
1270 What can I do?</title>
1273 First verify that it is indeed a <application>Privoxy</application> problem,
1274 by disabling <application>Privoxy</application> filtering and blocking.
1275 Go to <ulink url="http://p.p/">http://p.p/</ulink> and click on
1276 <quote>Toggle Privoxy On or Off</quote>, then disable it. Now try that
1277 page again. It's probably a good idea to flush the browser cache as well.
1281 If still a problem, go to <quote>Show which actions apply to a URL and
1282 why</quote> from <ulink url="http://p.p/">http://p.p/</ulink> and paste
1283 the full URL of the page in question into the prompt. See which actions are
1284 being applied to the URL. Now, armed with this information, go to <quote>Edit
1285 the actions list</quote>. Here you should see various sections that have
1286 various <application>Privoxy</application> features disabled for specific
1287 sites. Disabled <quote>actions</quote> will have a <quote>-</quote> (minus
1288 sign) in front of them. Add your problem page URL to one of these sections
1289 that looks like it is disabling the feature that is causing the
1290 problem. Re-try the page. There might be some trial and error involved. This
1291 is discussed in a little more detail in the
1292 <ulink url="../user-manual/appendix.html#ACTIONSANAT">user-manual
1298 Alternately, if you are comfortable with a text editor, you can accomplish
1299 the same thing by editing the appropriate <quote>actions</quote> file.
1305 <title>Where can I get help? Report bugs? Feature Requests? Etc?</title>
1307 Feedback is encouraged, whether good, bad or ugly. Please see the contact
1308 page in the <ulink url="../user-manual/contact.html">user-manual</ulink> for
1316 <title id="time">What time is it?</title>
1327 <!-- ~~~~~ New section ~~~~~ -->
1329 FIXME: Commented out until we have something to put here. HB 03/18/02.
1330 <sect1 id="knownissues"><title>Known Issues</title>
1337 <!-- ~~~~~ New section ~~~~~ -->
1340 This is referenced in the doc header already. HB 03/25/02
1342 <sect1 id="contact"><title>Contact the developers</title>
1343 <para>Please see the user manual for information on how to contact the developers.
1351 Tue 09/11/01 06:38:14 PM EST: Test SGML doc by Hal Burgiss.
1353 Last modified: Mon Sep 10 19:22:09 CEST 2001
1355 This program is free software; you can redistribute it
1356 and/or modify it under the terms of the GNU General
1357 Public License as published by the Free Software
1358 Foundation; either version 2 of the License, or (at
1359 your option) any later version.
1361 This program is distributed in the hope that it will
1362 be useful, but WITHOUT ANY WARRANTY; without even the
1363 implied warranty of MERCHANTABILITY or FITNESS FOR A
1364 PARTICULAR PURPOSE. See the GNU General Public
1365 License for more details.
1367 The GNU General Public License should be included with
1368 this file. If not, you can view it at
1369 http://www.gnu.org/copyleft/gpl.html
1370 or write to the Free Software Foundation, Inc., 59
1371 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
1374 Revision 1.37 2002/04/01 16:24:07 hal9
1375 -Rework of supported Q/A.
1376 -Set up entities to include boilerplate text.
1378 Revision 1.36 2002/03/31 23:18:47 hal9
1379 More on dealing with BLOCKED.
1381 Revision 1.35 2002/03/30 04:14:19 hal9
1382 Fix privoxy.org/config links.
1384 Revision 1.34 2002/03/29 04:35:56 hal9
1387 Revision 1.33 2002/03/29 01:31:48 hal9
1388 Several new Q/A's and other touch ups.
1390 Revision 1.32 2002/03/27 00:57:03 hal9
1391 Touch ups for name change.
1393 Revision 1.31 2002/03/26 22:29:55 swa
1394 we have a new homepage!
1396 Revision 1.30 2002/03/25 16:39:22 hal9
1397 A few new sections. Made all links relative to user-manual.
1399 Revision 1.29 2002/03/25 05:23:57 hal9
1400 Moved section, and touch ups.
1402 Revision 1.28 2002/03/25 04:27:33 hal9
1403 New section related to name change.
1405 Revision 1.25 2002/03/24 16:08:08 swa
1406 we are too lazy to make a block-built
1407 privoxy logo. hence removed the option.
1409 Revision 1.24 2002/03/24 15:46:20 swa
1410 name change related issue.
1412 Revision 1.23 2002/03/24 12:33:01 swa
1415 Revision 1.22 2002/03/24 11:51:00 swa
1416 name change. changed filenames.
1418 Revision 1.21 2002/03/24 11:01:06 swa
1421 Revision 1.20 2002/03/23 15:13:11 swa
1422 renamed every reference to the old name with foobar.
1423 fixed "application foobar application" tag, fixed
1424 "the foobar" with "foobar". left junkbustser in cvs
1425 comments and remarks to history untouched.
1427 Revision 1.19 2002/03/21 17:01:54 hal9
1430 Revision 1.18 2002/03/18 16:40:31 hal9
1433 Revision 1.17 2002/03/18 03:53:53 hal9
1436 Revision 1.16 2002/03/17 21:32:56 hal9
1437 A few more additions.
1439 Revision 1.15 2002/03/17 07:25:59 hal9
1440 Correcting some of my typos, and some additions.
1442 Revision 1.14 2002/03/17 02:39:13 hal9
1443 A little more added ...
1445 Revision 1.13 2002/03/17 00:22:20 hal9
1446 Adding new stuff, and trying to incorporate stuff from old faq.
1448 Revision 1.12 2002/03/11 20:13:21 swa
1451 Revision 1.11 2002/03/11 18:42:27 swa
1454 Revision 1.10 2002/03/11 13:13:27 swa
1455 correct feedback channels
1457 Revision 1.9 2002/03/10 23:34:04 swa
1458 more info on not hiding ip address
1460 Revision 1.8 2002/03/09 15:55:48 swa
1461 added default config section
1463 Revision 1.7 2002/03/07 18:16:55 swa
1466 Revision 1.6 2002/03/07 13:16:31 oes
1467 Committing changes by Stefan
1469 Revision 1.5 2002/03/02 15:50:04 swa
1470 2.9.11 version. more input for docs.
1472 Revision 1.4 2002/02/24 14:34:24 jongfoster
1473 Formatting changes. Now changing the doctype to DocBook XML 4.1
1474 will work - no other changes are needed.
1476 Revision 1.3 2001/09/23 10:13:48 swa
1477 upload process established. run make webserver and
1478 the documentation is moved to the webserver. documents
1479 are now linked correctly.
1481 Revision 1.2 2001/09/13 15:20:17 swa
1482 merged standards into developer manual
1484 Revision 1.1 2001/09/12 15:36:41 swa
1485 source files for junkbuster documentation
1487 Revision 1.3 2001/09/10 17:43:59 swa
1488 first proposal of a structure.
1490 Revision 1.2 2001/06/13 14:28:31 swa
1491 docs should have an author.
1493 Revision 1.1 2001/06/13 14:20:37 swa
1494 first import of project's documentation for the webserver.