Cameron Simpson wrote: [snip]
Tar files have a terminating record. To append you need to overwrite that record, and that you can't do in compressed state.
Fine. How do I get tar actually to append? I can compress later, if need be, I guess. Perhaps I'm asking amiss.
But I must be missing something. Why append to the tar file at all? Why not just make a lot of separate tar files?
Because I'm using CDROMs with K3b to write them, and I want as much on a single disc as possible, without a lot of fiddling to find which ones will fit with minimal wasted space. If I use a single file, and split it, I get no wasted space at all (except on the last disc, which is unavoidable). Ok, I'm asking about means rather than goals. Let me restate my desires. I want to make as few CDROMs as possible, with no wasted space (except on the last disc). So I want some kind of compression. I want a complete TOC (a la tar tvzf backup.tgz > backup.lst). I want progress reports via wall showing what directory is currently being worked (top level only, I don't want to know details, like /etc, /usr, /home, etc.). I want speed, as in not copying gigabyte files tens of times. If I can get tar to output progress reports like that via wall in more or less real time by other means than by appending, I'll be happy. If not, then I'd like a script loop which does the walls, and invokes tar multiple times, but only if I don't copy gigabyte files tens of times. Mike -- p="p=%c%s%c;main(){printf(p,34,p,34);}";main(){printf(p,34,p,34);} Oppose globalization and One World Governments like the UN. This message made from 100% recycled bits. You have found the bank of Larn. I can explain it for you, but I can't understand it for you. I speak only for myself, and I am unanimous in that!