files:
user.bayi1.kullaniciadi.tar.gz
user.bayi1.baskabirkullanici.tar.gz
must be renamed to:
user.bayi2.kullaniciadi.tar.gz
user.bayi2.baskabirkullanici.tar.gz
command:
for f in user.bayi1.*.tar.gz; do mv -v "$f" "${f/user.bayi1/user.bayi2}"; done;