Which (for admins)
The which command allows an administrator to determine which mailing lists a particular person belongs to.
The syntax of the which command is:
which emailaddress
You can specify as many email addresses on the which command line as you like.
For example, the follow commands are valid:
which bob@example.com
which jane@example.com albert@example.com
Note: If you do not first login as an administrator, the which command will tell you which lists you are on.