Was the "-h" flag ever a valid switch? The "-h" flag is not mentioned in the Wiki page for mkfs.btrfs [1].
In Ubuntu 12.04, "-h" is not a valid switch: $ mkfs.btrfs -h mkfs.btrfs: invalid option -- 'h' usage: mkfs.btrfs [options] dev [ dev ... ] options: -A --alloc-start the offset to start the FS -b --byte-count total number of bytes in the FS -d --data data profile, raid0, raid1, raid10 or single -l --leafsize size of btree leaves -L --label set a label -m --metadata metadata profile, values like data profile -n --nodesize size of btree nodes -s --sectorsize min block allocation Btrfs Btrfs v0.19 $ lsb_release -a No LSB modules are available. Distributor ID: Ubuntu Description: Ubuntu 12.04 LTS Release: 12.04 Codename: precise [1] https://btrfs.wiki.kernel.org/index.php/Mkfs.btrfs -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/961251 Title: mkfs.btrfs(8) does not explain -h switch To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/btrfs-tools/+bug/961251/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs