Command to get a group's quota
When external quota commands are being used, the program set in this option can be called by Virtualmin to fetch the quota for a single group. It is called with a single parameter - the Unix group name, and must output a single line containing the following space-separated fields :
  1. Current quota used in 1 kB blocks.
  2. The soft quota in 1 kB blocks, or 0 for unlimited.
  3. The hard quota in 1 kB blocks, or 0 for unlimited.
If this command is not set on the Module Config page, Virtualmin will use the Command to list group quotas instead.