Hi all,
I got interested in the archive format described at [1].
Is there still an interest in developing this format further and eventually replacing the use of TAR in Duplicity?
I have no particular experience with archive formats, but I have a couple of questions (some of which may be dumb):
* Is the inner index file (the one containing repeated metadata) supposed to come after the inner data file? I've attached a full diagram of the format to show the order of things. Is it correct?
* Why the division into such small (<= 65k) blocks at the outer level? Why not let each block at the outer level contain an entire inner data/index pair?
* The notes says: "Archive footer: Must contain all information in the header, in case the header is lost.". When would the header get lost?
* Would it not be useful to have some blocks compressed and some not (those corresponding to already compressed files)?
I saw in the archives that a few years ago someone suggested maybe using XAR [2], but got no response. Could that be an alternative or is there something missing that Duplicity would need? The XAR format seems quite badly documented though..
Best regards,
Elvis Stansvik