- From: Alex Rousskov <rousskov@measurement-factory.com>
- Date: Thu, 29 Apr 2004 12:03:56 -0600 (MDT)
- To: Lisa Dusseault <lisa@osafoundation.org>
- Cc: HTTP working group <ietf-http-wg@w3.org>
On Thu, 29 Apr 2004, Lisa Dusseault wrote: > Updates should be atomic -- the entire patch should be applied or > entirely failed. I will make that explicit. You may want to note in the draft that, in many cases, the atomicity requirement is expensive because it requires copying the entire content or "trying to patch" first, before actually patching, while holding the file lock. To avoid copying, a special --dry-run feature of the library/program that supports the given patch format would be needed. In fact, as the "internal error" part of the example below illustrates, copying may always be required for safe operation when the patch library/program does not guarantee atomicity: lock if patch --dry-run then if patch then unlock report success else internal error! revert to original content? ... fi else unlock error, report to the client fi Alex.
Received on Thursday, 29 April 2004 14:04:21 UTC