Epilogue: OK, I've reviewed Util.py. I can't find any evidence of serialization. I also reviewed the 'C' fopen() function with "a+" mode, and I also can't find any evidence of serialization.
My concern is if two processes try to append to the file at the same time. This is a low probability event, but under qmail it should be possible (for example, if two copies of tmda-filter run). I can't find a guarantee that the Util.append_to_file would be properly serialized. Thoughts? What am I missing or overlooking? Thanks, Dave. > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On > Behalf Of David T. Ashley > Sent: Wednesday, October 02, 2002 7:21 AM > To: [EMAIL PROTECTED] > Subject: Serialization And Unix File System Semantics Question > > > Hi, > > I have my whitelist "automagically" set up, i.e. > > CONFIRM_APPEND = os.path.expanduser("~/.tmda/lists/whitelist_confirmed") > > My understanding of qmail is that there are no guarantees on > serialization. > If two cofirmation e-mails arrive close to each other in time, there is no > guarantee that the two processes running won't try to append to the > whitelist at the same time. > > How is synchronization (i.e. writing collisions on the file) handled? Is > the "append" guaranteed atomic? > > Immediately after this, I'm gonna go digging in the Python scripts. > > Thanks a lot for any file serialization or process synchronization info. > > Dave. > > _____________________________________________ > tmda-users mailing list ([EMAIL PROTECTED]) > http://tmda.net/lists/listinfo/tmda-users > _____________________________________________ tmda-users mailing list ([EMAIL PROTECTED]) http://tmda.net/lists/listinfo/tmda-users
