On Wed, 23 Mar 2022 at 14:51, Casey Schaufler <casey@xxxxxxxxxxxxxxxx> wrote: > You also need a way to get a list off what attributes are available > and/or a way to get all available attributes. Applications and especially > libraries shouldn't have to guess what information is relevant. If the > attributes change depending on the filesystem and/or LSM involved, and > they do, how can a general purpose library function know what data to > ask for? Oh, yes. Even the current prototype does that: # ~/getvalues / "" [] = "mnt" "mntns" "xattr" "data" (len=21) # ~/getvalues / "mnt" [mnt] = "id" "parentid" "root" "mountpoint" "options" "shared" "master" "propagate_from" "unbindable" (len=76) # ~/getvalues / "mntns" [mntns] = "21" "22" "24" "25" "23" "26" "27" "28" "29" "30" "31" "32" (len=36) ~/getvalues / "mntns:21" [mntns:21] = "id" "parentid" "root" "mountpoint" "options" "shared" "master" "propagate_from" "unbindable" (len=76) I didn't implement enumeration for "data" and "xattr" but that is certainly possible and not even difficult to do. Thanks, Miklos