Robert Haas <robertmh...@gmail.com> writes: > On Tue, Apr 18, 2023 at 11:38 AM Tom Lane <t...@sss.pgh.pa.us> wrote: >> 2. The header size is defined as 512 bytes, but this doesn't sum to 512: >> + TAR_OFFSET_PREFIX = 345 /* 155 byte string */
> I think that what happened is that whoever designed the original tar > format decided on 512 byte blocks. And the header did not take up the > whole block. The USTAR format is an extension of the original format > which uses more of the block, but still not all of it. Hmm, you're right: I checked the POSIX.1-2018 spec as well, and it agrees that the prefix field is 155 bytes long. Perhaps just add another comment line indicating that 12 bytes remain unassigned? regards, tom lane