sysctl sounds like a good approach. It gets around the problem I mentioned
above correlating the OS device address with the device node. And it only
has to be used on tape drives that require the assign/unassign.
Whatever mechanism is used, it must prevent real I/O
(read/write/rewind/woef) to the device unless the latch is set properly.
The protocol would have to be something like:
1 - make the tape devices known to the host (insmod/modprobe/zipl.conf)
with devices unassigned
2 - sysctl assign a drive
a - if sysctl assign succeeds, allow I/O to the drive
b - if sysctl assign fails or has not been set, ALL I/O fails to the
drive
3 - sysctl unassign drive when user is finished with drive
Regards, Jim
Linux S/390-zSeries Support, SEEL, IBM Silicon Valley Labs
t/l 543-4021, 408-463-4021, [EMAIL PROTECTED]
*** Grace Happens ***
