I have a web page which shows a list of images. Users can click on a link next to each image to rotate them either left or right. The page is refreshed and the images re-displayed

The problem is, the images are being cached, so the previous orientation is being shown. I have tried setting the headers using CGI::Application as following (slightly modified from overkill anti-caching CGI headers):

    # Set a last-modified date a little in the future to handle
    # local workstation times being slightly out. Is that valid?
    my $date = DateCalc('today', '+ 5 minutes');
    $date = Date_ConvTZ($date, "", "GMT");

    $self->header_add(
        -expires       => 'Sat, 26 Jul 1997 05:00:00 GMT',
        -Last_Modified => UnixDate($date, '%a, %d %b %Y %H:%M:%S GMT')
+,
        # HTTP/1.0
        -Pragma        => 'no-cache',
        # HTTP/1.1
        -Cache_Control => join(', ', qw(
                no-store
                no-cache
                must-revalidate
                proxy-revalidate
                post-check=0
                pre-check=0
                max-age=0
                s-maxage=0
        )),
    );

[download]

An example of the produced header:

Date: Tue, 27 Mar 2007 03:52:20 GMT
Server: Apache/1.3.34 (Unix) mod_fastcgi/2.4.2 PHP/5.0.5
Expires: Sat, 26 Jul 1997 05:00:00 GMT
Pragma: no-cache
Last-Modified: Tue, 27 Mar 2007 03:52:20 GMT
Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-
+check=0
Keep-Alive: timeout=15, max=89
Connection: Keep-Alive
Content-Type: text/html; charset=utf-8
Transfer-Encoding: chunked

200 OK

[download]

This seems to work intermittently in Firefox on both Windows and Linux, and slightly less often in MSIE v6. Any ideas appreciated

In reply to Slightly OT: Stop caching images by astroboy

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