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diff --git a/docs/manual/custom-error.html b/docs/manual/custom-error.html deleted file mode 100644 index 09604ea972..0000000000 --- a/docs/manual/custom-error.html +++ /dev/null @@ -1,177 +0,0 @@ -<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN"> -<HTML> -<HEAD> -<TITLE>Custom error responses</TITLE> -</HEAD> - -<!-- Background white, links blue (unvisited), navy (visited), red (active) --> -<BODY - BGCOLOR="#FFFFFF" - TEXT="#000000" - LINK="#0000FF" - VLINK="#000080" - ALINK="#FF0000" -> -<!--#include virtual="header.html" --> -<H1 ALIGN="CENTER">Custom error responses</H1> - -<DL> - -<DT>Purpose - - <DD>Additional functionality. Allows webmasters to configure the response of - Apache to some error or problem. - - <P>Customizable responses can be defined to be activated in the - event of a server detected error or problem. - - <P>e.g. if a script crashes and produces a "500 Server Error" - response, then this response can be replaced with either some - friendlier text or by a redirection to another URL (local or - external). - <P> - -<DT>Old behavior - - <DD>NCSA httpd 1.3 would return some boring old error/problem message - which would often be meaningless to the user, and would provide no - means of logging the symptoms which caused it.<BR> - - <P> - -<DT>New behavior - - <DD>The server can be asked to; - <OL> - <LI>Display some other text, instead of the NCSA hard coded messages, or - <LI>redirect to a local URL, or - <LI>redirect to an external URL. - </OL> - - <P>Redirecting to another URL can be useful, but only if some information - can be passed which can then be used to explain and/or log the - error/problem - more clearly. - - <P>To achieve this, Apache will define new CGI-like environment - variables, <EM>e.g.</EM> - - <BLOCKQUOTE><CODE> -REDIRECT_HTTP_ACCEPT=*/*, image/gif, image/x-xbitmap, image/jpeg <BR> -REDIRECT_HTTP_USER_AGENT=Mozilla/1.1b2 (X11; I; HP-UX A.09.05 9000/712) <BR> -REDIRECT_PATH=.:/bin:/usr/local/bin:/etc <BR> -REDIRECT_QUERY_STRING= <BR> -REDIRECT_REMOTE_ADDR=121.345.78.123 <BR> -REDIRECT_REMOTE_HOST=ooh.ahhh.com <BR> -REDIRECT_SERVER_NAME=crash.bang.edu <BR> -REDIRECT_SERVER_PORT=80 <BR> -REDIRECT_SERVER_SOFTWARE=Apache/0.8.15 <BR> -REDIRECT_URL=/cgi-bin/buggy.pl <BR> - </CODE></BLOCKQUOTE> - - <P>note the <CODE>REDIRECT_</CODE> prefix. - - <P>At least <CODE>REDIRECT_URL</CODE> and <CODE>REDIRECT_QUERY_STRING</CODE> - will - be passed to the new URL (assuming it's a cgi-script or a cgi-include). - The - other variables will exist only if they existed prior to the - error/problem. - <STRONG>None</STRONG> of these will be set if your ErrorDocument is an - <EM>external</EM> redirect (<EM>i.e.</EM>, anything starting with a - scheme name - like <CODE>http:</CODE>, even if it refers to the same host as the - server).<P> - -<DT>Configuration - - <DD> Use of "ErrorDocument" is enabled for .htaccess files when the - <A HREF="mod/core.html#allowoverride">"FileInfo" override</A> is - allowed. - - <P>Here are some examples... - - <BLOCKQUOTE><CODE> -ErrorDocument 500 /cgi-bin/crash-recover <BR> -ErrorDocument 500 "Sorry, our script crashed. Oh dear<BR> -ErrorDocument 500 http://xxx/ <BR> -ErrorDocument 404 /Lame_excuses/not_found.html <BR> -ErrorDocument 401 /Subscription/how_to_subscribe.html - </CODE></BLOCKQUOTE> - - <P>The syntax is, - - <P><CODE><A HREF="mod/core.html#errordocument">ErrorDocument</A></CODE> -<3-digit-code> action - - <P>where the action can be, - - <OL> - <LI>Text to be displayed. Prefix the text with a quote ("). Whatever - follows the quote is displayed. <EM>Note: the (") prefix isn't - displayed.</EM> - - <LI>An external URL to redirect to. - - <LI>A local URL to redirect to. - - </OL> -</DL> - -<P><HR><P> - -<H2>Custom error responses and redirects</H2> - -<DL> - -<DT>Purpose - - <DD>Apache's behavior to redirected URLs has been modified so that additional - environment variables are available to a script/server-include.<P> - -<DT>Old behavior - - <DD>Standard CGI vars were made available to a script which has been - redirected to. No indication of where the redirection came from was - provided. - - <P> - -<DT>New behavior - <DD> - -A new batch of environment variables will be initialized for use by a -script which has been redirected to. Each new variable will have the -prefix <CODE>REDIRECT_</CODE>. <CODE>REDIRECT_</CODE> environment -variables are created from the CGI environment variables which existed -prior to the redirect, they are renamed with a <CODE>REDIRECT_</CODE> -prefix, <EM>i.e.</EM>, <CODE>HTTP_USER_AGENT</CODE> becomes -<CODE>REDIRECT_HTTP_USER_AGENT</CODE>. In addition to these new -variables, Apache will define <CODE>REDIRECT_URL</CODE> and -<CODE>REDIRECT_STATUS</CODE> to help the script trace its origin. -Both the original URL and the URL being redirected to can be logged in -the access log. - -</DL> -<P> -If the ErrorDocument specifies a local redirect to a CGI script, the script -should include a "<SAMP>Status:</SAMP>" header field in its output -in order to ensure the propagation all the way back to the client -of the error condition that caused it to be invoked. For instance, a Perl -ErrorDocument script might include the following: -</P> -<PRE> - : - print "Content-type: text/html\n"; - printf "Status: %s Condition Intercepted\n", $ENV{"REDIRECT_STATUS"}; - : -</PRE> -<P> -If the script is dedicated to handling a particular error condition, such as -<SAMP>404 Not Found</SAMP>, it can use the specific code and -error text instead. -</P> - -<!--#include virtual="footer.html" --> -</BODY> -</HTML> |