Use tar to append?

[Cameron Simpson]

On 08Mar2007 21:30, Les Mikesell <lesmikesell at gmail.com> wrote:
| Mike McCarty wrote:
| >I have a backup script which I run on some sort of regular
| >basis. I use tar to create an archive, which I then split
| >into pieces of CDROM size (703MB) and write to CDROMs.
| >
| >Originally, I wrote it such that it added directories one
| >by one to the archive, [...]
| >Is there a way to get tar to use the archive it is adding to
| >"in place"? I've read man and info, and I see --append
| >(which is what I was using) and --catenate (which looks
| >marginally faster, perhaps, since I compress), but see
| >no way to make it "just do it" without doing an implicit
| >copy.
| >
| 
| You can't append to an already gzipped file,

Yes you can. It's pretty handy.

Tar files have a terminating record. To append you need to overwrite
that record, and that you can't do in compressed state.

But I must be missing something. Why append to the tar file at all?
Why not just make a lot of separate tar files?
-- 
Cameron Simpson <cs at zip.com.au> DoD#743
http://www.cskk.ezoshosting.com/cs/

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