PATH_INFO does NOT return the URL for the called page, only any extra path data that was appended after the URL for the called page. Example (on Apache):

You have a page on url http://localhost/test.shtml that includes (with #exec cgi) /script.cgi and you call this with http://localhost/test.shtml/extra/path?param=1 you get the following:

REQUEST_URI  = /test.shtml/extra/path?param=1
PATH_INFO    = /extra/path
QUERY_STRING = param=1
SCRIPT_NAME  = /script.cgi
DOCUMENT_URI = /test.shtml/extra/path
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Unfortunately (on Apache), there seems to be no environment variable that shows only the URI of the called shtml page (should be /test.shtml here) if the request contains extra path_info.

Your best bet would probably be to remove $ENV{PATHINFO} from $ENV{DOCUMENT_URI}.

Please note that SSI support and implementation varies betweeen different (versions of) webservers, so you probably should test all this yourself by including a test script in a shtml page like this:

#!/usr/bin/perl

print "Content-type: text/plain\n\n";
for (sort keys %ENV) {
        print "$_ : $ENV{$_}\n";
}
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Also note that using CGI.pm may change the value of certain environment variables. YMMV.

-- 
Joost       downtime n. The period during which a system
            is error-free and immune from user input.
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