Re: [naviserver-devel] [naviserver-commits] naviserver ChangeLog, 1.405, 1.406

[Zoran V. <zv...@ar...>]

Am 30.06.2006 um 19:50 schrieb Vlad Seryakov:

> To mimic Tcl variables usage or any memory access operations, by  
> having
> _set, _get, _exist, _unset with additional _eval will make it complete
> and will allow to use by the developer as he sees fit. These are basic
> operations, on top of that a developer can build different systems,  
> not
> just one way. It is development tool, not complete system, we can  
> never
> anticipate all possible usages of cache API, so providing low-level
> primitives in my opinion is good direction.

Be it. I do not have anything against. Developers should be warned
though that exists/get or exists/set or any combianation of those
must be protected by external mutex to avoid race conditions.
In that case, one should/would add something like:

   ns_cache_lock cachename {
      do whatever with the cache
   }

which needs to be a recursive lock, OR

   ns_cache_lock cachename
   ns_cache_unlock cachename

in which case developer should exercise caution
to make sure to unlock the cache at all costs even
in case of Tcl error happening between lock/unlock calls.

So. This is what I must add to it.

Cheers,
Zoran