Required Directories

[Chuck Swiger]

On May 26, 2008, at 9:54 AM, Andrew Pantyukhin wrote:
>> It's generally not expected that users would not own the stuff
>> under their homedir, or would not be able to delete their files
>> if they want to, even if doing so would break something.
>> Normally, sysadmins code their scripts to re-create any missing
>> directory hierarchy if needed, so that if a user manages to
>> shoot themselves in the foot, the cron jobs will be able to
>> provide first aid.
>
> I don't know what kind of sysadmins you're talking about, but,
> say, if a hoster did not support files with non-ascii names, but
> let me upload them and then just remove them automatically, I
> would not be happy.  Preventive policies work better for me.

Hmm.  While you seem to have written in response to what I'd said, I'm  
not entirely sure I follow the connection...?

If I were a user who had a need to create non-ASCII filenames, then I  
would select a platform or hosting environment which could do exactly  
that, rather than selecting a platform or hosting environment which  
didn't provide a needed capability.  It took two hops into Wikipedia  
to dig the following out:

   http://en.wikipedia.org/wiki/Comparison_of_file_systems#Limits

If I were a user that needed to create non-ASCII filenames and was  
forced to use a platform which didn't support Unicode, well, I  
wouldn't be happy even if it refused to let me upload my files without  
renaming them, but sure, I suppose that I agree that it would be worse  
if it deleted my files after letting me upload them.

I like systems which don't break better than ones which do and need to  
be fixed.  I like systems which can fix themselves better than ones  
which can't tolerate recoverable errors and need human babysitting.   
Lots of people write scripts.  Good scripts perform some level of  
sanity checking and they set up the environment they need to work  
instead of assuming that the existing situation is correct.  They  
might provide guards against excessive concurrency by using lockfiles,  
they might recognize common modes of failure and deal with them (even  
if it is by logging an alert for a human and then bailing) and so forth.

Anyway, using filesystem ACLs or flags to make the directories un- 
deletable is probably a better solution for Grant's situation than  
using the sticky bit or immutable flag.

-- 
-Chuck