On Sun, Nov 5, 2017 at 4:07 PM, Pali Rohár <pali.rohar@xxxxxxxxx> wrote: > On Sunday 05 November 2017 15:56:53 Andy Shevchenko wrote: >> On Sun, Nov 5, 2017 at 3:39 PM, Pali Rohár <pali.rohar@xxxxxxxxx> wrote: >> > On Tuesday 31 October 2017 10:35:48 Andy Shevchenko wrote: >> >> On Mon, Oct 16, 2017 at 4:12 AM, Andreas Bombe <aeb@xxxxxxxxxx> wrote: >> >> > On Thu, Oct 12, 2017 at 10:49:31PM +0200, Pali Rohár wrote: >> >> >> On Thursday 12 October 2017 12:13:11 Karel Zak wrote: >> >> >> > I was worried that there might be some scripts or programs that expect >> >> >> >> If we really care about such scripts another approach might be to >> >> introduce a CLI switch to "spec compatible mode" to each tool and >> >> suggest in documentation to use it. >> >> >> >> There are also variants: >> >> - spec compatible >> >> - WinXX compatible >> >> - DOS compatible >> >> - etc >> > >> > I did tests with MS-DOS and Windows versions (results in previous >> > email), and they seems to be compatible how they read label. >> > >> > Based on results I would suggest to ignore label from the boot sector >> > when reading label. >> >> So, for tools which are not doing that to add >> >> --ignore-boot-sector-label (or alike) [recommended] >> >> right? >> >> We don't actually know how many users (scripts) are relying on current >> behaviour. >> If there are only few, we may introduce backward compatibility switch >> >> --read-boot-sector-label > > Current behavior of the last blkid and fatlabel tools is: Try to read > label from the root directory. If it does not exist, then fallback to > label stored in boot sector. And when fatlabel is changing label it > updates both locations. > > So tools which already uses fatlabel for get & set operations should not > be affected as setting new label makes boot and root in sync. > > New proposed behavior is: Try to read label from the root directory. If > not exist, then treat disk as without label. > > As in current behavior there is no way via fatlabel to read "just only > label from boot sector", I think that problems for current scripts is > minimal. > > What about making this new behavior in fatlabel as default with new > switch --fallback-to-boot-sector (switch to current behavior) or > --read-only-boot-sector (ignores label in root directory) for people who > are interested in label stored in boot sector? Dunno how others will react, but I think what you are proposing makes sense. > And what to do with blkid? That cannot have any switch :-( and can have > only one behavior. Btw, I don't see such tool in Debian unstable. Do you mean libblkid ? lsblk OTOH has switches. >> > This makes behavior consistent with older MS-DOS >> > systems and also all Windows systems. This change would be a problem >> > only for users who have label stored only in boot sector. After change >> > they would not see label anymore -- exactly same what MS-DOS or Windows >> > show them. Seems that mkdosfs stores label to both location, since >> > support for label was introduced. So different label would be visible >> > only for users who used dosfslabel prior to version 3.0.16. >> > >> > What do you think? >> >> So, in summary it looks like a documentation needs update (to mark >> your research). > > Which documentation do you mean? At least dosfstools (to mark that versions prior 3.0.16 better to avoid). And any where new switch would have been added and / or default behaviour would have been changed. -- With Best Regards, Andy Shevchenko -- To unsubscribe from this list: send the line "unsubscribe util-linux" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
