[pmwiki-users] Cannot acquire lockfile

[Marc Cooper]

Patrick R. Michaud said...
> On Fri, Sep 08, 2006 at 07:27:25PM +0100, Marc Cooper wrote:
> > Hi,
> > 
> > I just installed PmWiki 2.1.24 in a userdir - I usually run it from the 
> > serverroot on Linux or a Windows' userdir, so this is a first, I think.
> > 
> > After manually creating /wiki.d and /uploads, perms are 755, I get ye 
> > olde message:
> > 
> >  Cannot acquire lockfile
> > 
> > I can sidestep this by setting 777 or similar, but that's not what I 
> > want to do. I've checked that PHP safe_mode is off.
> 
> Short answer:
> If you manually create the directories, their permissions have to be
> 777.  The only real way to avoid 777 permissions on the directories
> is to let the webserver create them instead of manually doing it.

Hi Patrick,

This isn't a deal breaker for me - far, far from it ;-)

However, when I searched for a 'fix', I found a lot of half-solutions, 
and quite a few links to busted PmWikis! So, in part, this is an attempt 
to put the 'right way' out there.
 
> Longer answer:
> 
>   - In order to work, PmWiki has to be able to create files in the
>      wiki.d/ directory.
> 
>   - In a standard Apache/Unix environment, when PmWiki runs, it runs 
>     under the webserver account.  Usually this is something like
>     'apache', 'www', or 'nobody'.
> 
>   - Ignoring unix groups, the only way a program running under a
>     webserver account can create a file in a directory is if either
>       (a) the webserver account owns the directory
>       (b) the directory has "other" write permissions (i.e., 777)
> 
> I know it stinks for things to be this way, but I'm not 
> responsible for the way that Apache works.  

:-)

> On the good side, if you let PmWiki create directories, it will
> give the directories and files it creates the minimum permissions
> needed to preserve access for itself and the account owner.  Thus,
> if the wiki.d/ and uploads/ directories can be setgid (to the same
> group as the owner), then the files will end up without world write
> access.

Right. I wasn't sure what you meant, precisely, by this, so I opened 
'tother machine, deleted wiki.d, and noticed that you spell it out in 
the error message - somehow I missed this yesterday, but, of course, I 
will swear that it wasn't there then ;-)

So, for the record:

1. chmod 2777 ~/public_html
2. Load/reload pmwiki.php
3. chmod 0755 ~/public_html
4. All done

-- 
Best,
Marc