[CalendarServer-dev] Re: twisted dav : xattrprops on linux

[Vincent Kraeutler]

i agree. i have found this extra little tidbit:
http://www.penguin-soft.com/penguin/man/5/attr.html

i.e. it seems like xattrs are also used for storing
permission bits, ACL's etc. on some platforms. i.e.
information that sometimes should not be modifiable
by the owner of the file.

i'm not sure i'm happy about the way it seems to be
implemented, and i agree with you that it's likely
not worth introducing an extra wart (especially since
it's very easy to override deadPropertyXattrPrefix later
on), but i certainly wanted to have it mentioned.

all the best,
v.

Wilfredo Sánchez Vega wrote:
>   (Let's chat on the mailing list; I don't always respond to direct
> mail, get too much and all that.)
>
>   That's a weird rule...
>
>   Does it make sense for this to be hidden in the xattr library? 
> Perhaps not...  I kinda hate to so this on OS X just because Linux is
> weird.
>
>     -wsv
>
>
> On Sep 9, 2006, at 9:52 AM, Vincent Kraeutler wrote:
>
>> wilfredo,
>>
>> just stumbled across what looks like a minor issue with
>> xattrs on linux: it seems that when writing xattrs, normal
>> users are _required_ (at least on ext2/ext3) to prefix all
>> attribute names with "user.". i.e. it is not possible to
>> carry out
>>
>>>> import xattr
>>>> xx = xattr.xattr("testFile")
>>>> xx["foo"] = "bar"
>>
>> while
>>
>>>> xx["user.foo"] = "bar"
>>
>> works. if that is indeed the case, i would be tempted to suggest
>> prefixing
>> twisted.web2.dav.xattrprops.xattrPropertyStore.deadPropertyXattrPrefix
>> with "user.", i.e. replace "WebDAV:" with "user.WebDAV:" to enhance
>> portability.
>>
>> i hope i am making sense.
>>
>> kind regards,
>> v.
>>
>>
>