The whole environment
CONTEXT_DOCUMENT_ROOT /public/homepages/neilb/cgi
CONTEXT_PREFIX /cgi/neilb
DOCUMENT_ROOT /public/homepages/homepages-data/web
GATEWAY_INTERFACE CGI/1.1
HTTP_ACCEPT text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
HTTP_ACCEPT_ENCODING gzip
HTTP_CONNECTION Keep-Alive
HTTP_HOST homepages.inf.ed.ac.uk
HTTP_IF_MODIFIED_SINCE Thu, 24 May 2018 15:31:44 GMT
HTTP_USER_AGENT CCBot/2.0 (https://commoncrawl.org/faq/)
PATH /usr/local/bin:/usr/bin:/bin
QUERY_STRING 
REMOTE_ADDR 54.80.208.105
REMOTE_PORT 58454
REQUEST_METHOD GET
REQUEST_SCHEME http
REQUEST_URI /cgi/neilb/allenv.pl
SCRIPT_FILENAME /public/homepages/neilb/cgi/allenv.pl
SCRIPT_NAME /cgi/neilb/allenv.pl
SCRIPT_URI http://homepages.inf.ed.ac.uk/cgi/neilb/allenv.pl
SCRIPT_URL /cgi/neilb/allenv.pl
SERVER_ADDR 129.215.32.113
SERVER_ADMIN webadmin@inf.ed.ac.uk
SERVER_NAME homepages.inf.ed.ac.uk
SERVER_PORT 80
SERVER_PROTOCOL HTTP/1.1
SERVER_SIGNATURE 
SERVER_SOFTWARE Apache/2.4
UNIQUE_ID W3iSGygvjUudFr8f595zDwAAAC4

The End.

Explicit variables

DOCUMENT_URI = 

#ARGV = -1
STDIN
End STDIN

ldapsearch test - get web/wiki/dice members  - 3848 entries in 0s

What follows is an SSI to test if it is interpreted.
The date is: Saturday, 18-Aug-2018 22:39:39 BST

This was included from ssi/test.inc