Ken wrote: > - The "complex" case, where the sequence file could > potentially be changed from the time that it's first > read until the sequence file needs to be manipulated. > "inc" is an example; "pick" is another.
Is sortm in the same category as folder -pack? > The basic issue there is if you add a new message to a > folder, the long-running command wouldn't necessarily know > the new message existed and thus when it wrote the new > sequence file out it wouldn't write out any sequences that > these new messages are in. I'm worried about something else: concurrent read/write of the sequences file. If two or more processes read it and write it concurrently, the last one to write will destroy everything that the other processes wrote. Locked-read- write will detect that, but I'm not sure we can always correct it. I don't have a concrete example of where we can't, but it feels analogous to a merge conflict. > adding new messages to a folder that you're currently > inc'ing into is already not safe (messages could get > overwritten). How so? It depends what "adding" means, but I would limit that to just nmh commands that can add a new message. I think that's inc, refile, rcvstore, burst, and thing that fcc's (comp, dist, forw, repl, mhmail). And I don't think they'll overwrite a message that any other, even non-nmh, program had created. David _______________________________________________ Nmh-workers mailing list [email protected] https://lists.nongnu.org/mailman/listinfo/nmh-workers
