Problems with mt and Exabyte in SUNOS 4.0.3

[Rich Winkel UMC Math Department]

It seems that when the last operation on /dev/nrst9 is a write of any kind,
doing an 'mt status' indicates that the tape is positioned at file number 1,
regardless of where it really is.  Subsequently doing an 'mt bsf' causes it
to do a rewind to the beginning of the tape, which can be a pain.
What I'm trying to do is make sure that the tape is positioned past the last
file, before doing a dump.  Doing an 'mt eom' when it's already positioned
past the last file causes it to run to the end of the tape, so I tried an
'mt bsf' followed by 'mt eom'.  Unfortunately, if the last tape operation was
the previous dump, the 'bsf' causes it to rewind to the beginning, and 'eom'
takes forever to complete when there are a number of files on the tape.
Is it supposed to behave this way?
Can someone send a code fragment using ioctl to position a scsi tape drive?

Thanks!
Rich Winkel
MATHRICH at UMCVMB.MISSOURI.EDU