- [ -f /etc/apt/sources.list -a ! -f /etc/apt/sources.list.cn4-upgrade ] && mv /etc/apt/sources.list /etc/apt/sources.list.cn4-upgrade
- cp /usr/share/carnet-upgrade/files/etc/apt/sources.list /etc/apt
- notice "Novi sadrzaj datoteke /etc/apt/sources.list:
+ local sl sl_new
+ sl=/etc/apt/sources.list
+ sl_new=/usr/share/carnet-upgrade/files/etc/apt/sources.list
+
+ # check if already installed
+ if ! cmp $sl $sl_new >/dev/null; then
+
+ # backup old version
+ if [ -f $sl -a ! -f $sl.$backup_ext ]; then
+ cp $sl $sl.$backup_ext
+ fi
+
+ # install new version
+ cp $sl_new $sl
+ notice "Novi sadrzaj datoteke /etc/apt/sources.list: