All VMS labeled tapes must be initialized before their first use, or reinitialized to put different files on the tape. ALL allows other users to read, write, and initialize the tape. READ allows other users to read the tape but not write or initialize the tape.
NONE allows other users to neither read, write, nor initialize the tape.
The default is 6250. U9999 Initializes tape U9999 with READ protection and 6250 bpi density. The tape is dismounted and the drive is deallocated. The tape is dismounted, but the drive is still allocated. Initializes tape U9999 with READ protection and 6250 bpi density.