Specifying multi-domain jails in Gollem FTP

Not exactly documented, most people may assume that setting an FTP jail is restricted to absolute paths in Gollem's backend.php .

This is clearly not suitable for servers where users log into virtual sites under different domains. Two styles of jails are then desired:

1. The user is restricted to /path/to/site-root/home/user
   1. The user is restricted to /path/to/site-root (suitable for site owners)

Trouble is, the site-root location is a variable.

(section describing userhome-relative paths for root and home deleted)

(later...)

Turns out the problem was wrongly posed.

• FTP jail is normally handled by the FTP server in its configuration. proftp for example allows domain-specific jails. Fine.
  • Problem is actually to dynamically set 'hostspec' to be the current user's domain so that one-click login to ftp works with correct ftp-server-resolving of appropriate jail root.

Is for example the current domain running horde available as

'hostspec' => $GLOBALS['something...'],

For that matter, is there any quick way to see what global values are available?