Re: Imagemaps problem - need help

John Labovitz (johnl@ora.com)
Sat, 12 Nov 94 10:24:36 -0800


Message-Id: <199411121824.KAA29590@rock>
To: GSTANIAK@golem.umcs.lublin.pl
Cc: Multiple recipients of list <www-html@www0.cern.ch>
Subject: Re: Imagemaps problem - need help 
In-Reply-To: Your message of "Sat, 12 Nov 94 15:18:50 +0100."
             <23720E64EAE@golem.umcs.lublin.pl> 
Date: Sat, 12 Nov 94 10:24:36 -0800
From: John Labovitz <johnl@ora.com>

GSTANIAK@golem.umcs.lublin.pl:
>      <A HREF="http://www.my.place/path/to/map/map_file.map">
>      <IMG SRC="/path/to/gif/map.gif" ISMAP></A>.

this should be:

       <A HREF="http://www.my.place/cgi-bin/imagemap/alias">
       <IMG SRC="/path/to/gif/map.gif" ISMAP></A>.

(`alias' being the left-hand part of the specific
line in your `imagemap.conf' file that points to
`map_file.map'.)

the server (at least, the ncsa httpd server) doesn't
know about imagemaps internally, so it doesn't call
the imagemap program automatically.  by setting the 
ISMAP attribute in your <IMG> tag, you're telling
the *client* to send coordinates along with the URL
request in the <A> tag.  the server receives this as

  GET /cgi-bin/imagemap/alias?x,y

and does as it's told -- runs the `imagemap' program
in the `cgi-bin' directory.  the server gives the 
imagemap program the $PATH_INFO of `alias' and the 
$QUERY_STRING of `x,y'.  imagemap looks up `alias'
in its config file, opens the appropriate map file 
and does the coordinate-to-URL conversion.

you are in a maze of twisty little passages, 
all alike. ;-)

--
John Labovitz
Global Network Navigator <http://gnn.com/>
O'Reilly & Associates, Sebastopol, California, USA (+1 707 829 0515)