UNIX for Dummies Questions & Answers

Hello,

I am wondering if there is an easy way to add a file to a tarball rather than extracting, adding, then remaking the tarball.

The tarball was made in this way:

Code:

tar -cpvzf .wine.tar.gz .wine/

If I had a file to the .wine/ dir (or if I just wanted to add a file to the tarball), I would like to add it to .wine.tar.gz rather than having to un(tar/gzip) it, add it to the dir, and then re-tarball it (yes I know I could just add it to .wine/ then redo the above command; I'm just looking to understand principles, here, as if I deleted the dir after I tarballed it).

With thanks,
Narnie

Code:

gunzip .wine.tar.gz
tar -Avf .wine.tar [more files - directories]
gzip wine.tar

So I take it there is no way to do what I was asking? It must be decompressed with gunzip, appended, the re-gzipped? Too bad it can't work more like zip files, of course in other ways, tar is much more powerful.

I'm curious tho, in what I've read in the past about tarballing, if it is tarballed using the -z argument, each file is individually gzipped then added to the tar. I was reading a text written in 1999, tho (SAM'S teach yourself shell programming in 24 hours, which was an excellent starting point).

I just tried the above and, of course, it worked. So has the behaviour of the -z arg changed to adding all the files to the tar then gzipping it? I'm curious because this has implications in creating a large tar file that if it were done along the way would be smaller vs creating a tar, then gzipping, which might create storage problems.

Thanks for you patience,
Narnie

if you have access to GNU tar, you can use --append (-r)

---------- Post updated at 04:02 PM ---------- Previous update was at 03:59 PM ----------

sorry, scratch that - you can do it w/ tar or gtar (instead of tar cf tarfile file1 file2 etc. do tar rf tarfile newfiletoadd)

Doesn't work on compressed files as above. The output for viewing pleasure

Code:

$ tar rf test.tar.gz test2
tar: Cannot update compressed archives
tar: Error is not recoverable: exiting now

I'll just write a script and gunzip it and gzip it back. Thanks all. Was hoping for a more elegant soln. Perhaps this is what zip programs do in the background anyway.

Yours,
Narnie