Modifying Linux in WesternDigital net disks

Hi,
I am installing perl and rsnapshot on the OS of a Western Digital MyBook disk.
To install perl the ./Configure command tells me that both 'tr' and 'split' are missing. I don't find them on the net.
Where can I download them?
Thanks.
Charles.

GNU coreutils...source is here or you can probably download binaries for your platform (for example here)

Thks
Charles

---------- Post updated at 12:10 PM ---------- Previous update was at 10:35 AM ----------

I found this too
to install utilities on this kind of systems
OPTWARE very good package

mybookworld.wikidot.com/optware

Cheers.