Related to disk quota management is the simpler question of how much disk space is available on the system. The df command reports disk usage on a per-disk basis, but the output can be a bit baffling:

$ df
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/hdb2 25695892 1871048 22519564 8% /
/dev/hdb1 101089 6218 89652 7% /boot
none 127744 0 127744 0% /dev/shm

What would be much more useful is a version of df that summarizes the available capacity values in column four and then presents the summary in a way that is easily understood. It’s a task easily accomplished in a script.

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