This is a socket which is not reachable from the Internet directly, but
which must come from a request on your own server. The link program
vlink is the provided facility for such communication with MiniVend.
This is the most secure way to run your catalog, for there is no way for systems on the Internet to interact with MiniVend except through its link program.
The most important issue with UNIX-domain sockets on MiniVend is the permissions with which the CGI program and the MiniVend server run.
To improve security, MiniVend normally runs with the socket file having 0600 permissions (rw-------), which mandates that the
CGI program and the server run
as the same user ID. This means that the vlink program must be
SUID to the same user
ID as the server executes under. (Or that
CGIWRAP is used on a single catalog system).
With MiniVend multiple catalog capability, the permissions situation gets a
bit tricky. MiniVend comes with a program, makecat, which configures catalogs for a multiple catalog system. It should
properly set up ownership and permissions for multiple users if run as the
superuser.