( As pr usual no root privileges required for ports above 1024 )
As not everyone has FileMaker Server running, here is a way to check to see what the query does.
$ nc -l -p 8180
POST /fmi/xml/fmresultset.xml HTTP/1.1
Host: 127.0.0.1:8180
Authorization: Basic d2ViOndlYg==
Accept: */*
Content-Type: application/x-www-form-urlencoded;charset=UTF-8
Content-Length: 8
-dbnames
or nc -l -p 8180 | xxd
Prerequisit: