Append files to a existing tar file.

Shell Programming and Scripting
1

Hi all,

I want to check whether tar file exists in the directory or not. If tar file exists in the directory then I want to append the files to it.

I am using the below command to tar files if the file does not exist.

tar zcvf <tar file name> <Files to append>

However, if want to append some more files to the existing tar file with above command, files in the tar are getting deleted.

I tried using the below command but I am getting error as below.
"tar: You may not specify more than one `-Acdtrux' option"

tar zcvfr <tar file name> <additional files to append>

Request you to provide the code for file check and tar command if tar file exists.

Thanking you in advance.
Nagaraja Akkivalli.

Thanks and Regards
Nagaraja Akkivalli.

2

I'd think you want 'u' (update existing) instead of 'c' (create new) in your flags for tar.

As a little aside, you may also want to drop the z flag and pass the tar through a compression program of your choice - that way it'll work with non-gnu versions of tar and/or opens up the option to use better compression like bzip.

1 Like
3

Thanks Smiling Dragon for you response..!!

Let me explain it clearly....

Say, tar ABC.tgz has a.dat, b.dat and c.dat in it. If I want to add one more file(d.dat) to it then tar should not overide the existing file content. After taring 4th file then it should have all 4 (a.dat, b.dat and c.dat, d.dat) files.

Can I assume "update existing" does the same as I explained above?

Can you plz share the piece of code if you have or can you point to link where I can get this?

Thanks and Regards
Nagaraja Akkivalli

4

One more update.

I used below command if tar file existing.

tar rvf <tar file name> <additional files to append> ,

tar command was successful but when I untarred it, tar had only one file which was tarred first.

Please see the below code.

[user@dbname processed 04:31:05 AM]$tar zcvf FileName122011.tgz FileName_20110325101.dat
FileName_20110325101.dat
[user@dbname processed 04:31:05 AM]$tar rvf FileName122011.tgz FileName_20110325102.dat
FileName_20110325102.dat
[user@dbname processed 04:31:05 AM]$ls -ltr For*
-rwxrwSrwt 1 root root 402 Jul 16 02:48 FileName_20110519054238_0.dat
-rwxrwSrwt 1 root root 402 Jul 16 02:48 FileName_20110519053824_0.dat
-rwxrwSrwt 1 root root 415 Jul 16 02:48 FileName_20110519EP_vaL_2.dat
-rwxrwSrwt 1 root root 608 Jul 16 02:48 FileName_20110602031917_0.dat
-rwxrw-r-x 1 root root 416 Jul 17 11:42 FileName_20110325101.dat
-rwxrwSr-t 1 root root 416 Jul 17 11:51 FileName_20110325102.dat
-rwxrwxrwx 1 root root 10618 Jul 17 11:53 FileName122011.tgz
[user@dbname processed 04:31:05 AM]$rm -rf FileName_20110325102.dat
[user@dbname processed 04:31:05 AM]$rm -rf FileName_20110325101.dat
[user@dbname processed 04:31:05 AM]$ls -ltr For*
-rwxrwSrwt 1 root root 402 Jul 16 02:48 FileName_20110519054238_0.dat
-rwxrwSrwt 1 root root 402 Jul 16 02:48 FileName_20110519053824_0.dat
-rwxrwSrwt 1 root root 415 Jul 16 02:48 FileName_20110519EP_vaL_2.dat
-rwxrwSrwt 1 root root 608 Jul 16 02:48 FileName_20110602031917_0.dat
-rwxrwxrwx 1 root root 10618 Jul 17 11:53 FileName122011.tgz
[user@dbname processed 04:31:05 AM]$tar zxvf FileName122011.tgz
FileName_20110325101.dat
gzip: stdin: decompression OK, trailing garbage ignored
tar: FileName_20110325101.dat: Cannot utime: Operation not permitted
tar: Child returned status 2
tar: Error exit delayed from previous errors
5

This is how I did it.

If tar file does not exists use below command.
tar -cvf <tar-file-name.tar> < files to be added>

If tar file exists then use.
tar -rf <tar-file-name.tar> < files to be append>

Thanks
Nagaraja