Adding file to an existing tar

Shell Programming and Scripting
1

Hi Friends,
I want to know the command to add a new file in a existing tar file.

For Ex:
I have a tar file file1.tar with the contents
one.txt
two.txt
three.txt

Now I need to add file four.txt to this existing tar file, how can I do it?

Thanks in advance

2

check for -r flag in tar man pages.

3

-r doesn't work in my system . I work with IBM AIX 5.3

4

Do you have -u flag?

for example:

tar -u four.txt -f file1.tar

5

check with tar manal
$man tar

 -r      Append the named new files to existing archive.  Note that this
         will only work on media on which an end-of-file mark can be over-
         written.

-u Alias for -r.

Else whatever you have on system ..