I have multiple tar's that I want to untar into a folder and then append a prefix to them. The problem is that I don't know the name of the folder that it would create on the target system since these are build tar's and they have a date-timestamp inside. Here is what I tried -

```
tar xfz <filename>-*.tar.gz -C $UNTAR_LOCATION 

```

so this creates a folder like this `20140909-0900` on the target `UNTAR_LOCATION`. How can I append a prefix to the date-timestamp ?

Note - there will be multiple folders with different date-timestamps under `UNTAR_LOCATION` for which I want to add the same prefix.