df
Filesystem     1K-blocks    Used Available Use% Mounted on
udev             1945428       0   1945428   0% /dev
tmpfs             393328    1348    391980   1% /run
/dev/sdb1       30456832 1967424  28489408   7% /cdrom
/dev/loop0       1880320 1880320         0 100% /rofs
/cow             1966632   69244   1897388   4% /
tmpfs            1966632   19604   1947028   1% /dev/shm
tmpfs               5120       4      5116   1% /run/lock
tmpfs            1966632       0   1966632   0% /sys/fs/cgroup
tmpfs            1966632     504   1966128   1% /tmp
tmpfs             393324      28    393296   1% /run/user/999