$ ./disk-usage.sh
Threshold = 12
WARNING: Partition "/dev/nvme0n1p6" used 13%
WARNING: Partition "/dev/nvme0n1p1" used 27%

$ ./disk-usage.sh
Threshold = ceva
WARNING: Partition "/dev/nvme0n1p6" used 30%
WARNING: Partition "/dev/nvme0n1p1" used 31%