On Mon, Apr 4, 2011 at 12:47 PM, Goffredo Baroncelli <kreij...@libero.it> wrote: > On 04/04/2011 09:09 PM, krz...@gmail.com wrote: >> I understand btrfs intent but same command run twice should not give >> diffrent results. This really makes snapshot automation hard >> >> >> root@sv12 [/ssd]# btrfs subvolume snapshot /ssd/sub1 /ssd/5 >> Create a snapshot of '/ssd/sub1' in '/ssd/5' >> root@sv12 [/ssd]# btrfs subvolume snapshot /ssd/sub1 /ssd/5 >> Create a snapshot of '/ssd/sub1' in '/ssd/5/sub1' >> root@sv12 [/ssd]# btrfs subvolume snapshot /ssd/sub1 /ssd/5 >> Create a snapshot of '/ssd/sub1' in '/ssd/5/sub1' >> ERROR: cannot snapshot '/ssd/sub1' > > The same is true for cp: > > # cp -rf /ssd/sub1 /ssd/5 -> copy "sub1" as "5" > # cp -rf /ssd/sub1 /ssd/5 -> copy "sub1" in "5" > > However you are right. It could be fixed easily adding a switch like > "--script", which force to handle the last part of the destination as > the name of the subvolume, raising an error if it already exists. > > "subvolume snapshot" is the only command which suffers of this kind of > problem ?
Isn't this a situation where supporting a trailing / would help? For example, with the / at the end, means "put the snapshot into the folder". Thus "btrfs subvolume snapshot /ssd/sub1 /ssd/5/" would create a "sub1" snapshot inside the 5/ folder. Running it a second time would error out since /ssd/5/sub1/ already exists. And if the 5/ folder doesn't exist, it would error out. And without the / at the end, means "name the snapshot". Thus "btrfs subvolume snapshot /ssd/sub1 /ssd/5" would create a snapshot named "/ssd/5". Running the command again would error out due to the snapshot already existing. And if the 5/ folder doesn't exist, it's created. And it errors out if the 5/ folder already exists. Or, something along those lines. Similar to how other apps work with/without a trailing /. -- Freddie Cash fjwc...@gmail.com -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
