| CH(4) | Kernel Interfaces Manual | CH(4) | 
NAME
 ch — SCSI media changer driver
SYNOPSIS
 ch* at scsibus? target ? lun ?
DESCRIPTION
 The 
ch driver is essentially an 
ioctl(2) interface to a robot on a SCSI bus - a device that will change media (e.g. tapes, CD-ROMs, etc) in and out of drives for that media. The 
chio(1) utility program uses this interface to manipulate such robots.
 
FILES
- 
/dev/chu
- 
SCSI bus media changer unit u
/usr/include/sys/chio.h 
DIAGNOSTICS
- 
ch%d: waiting %d seconds for changer to settle...
- 
Some changers require a long time to settle out, to do tape inventory, for instance.
- 
ch%d: offline
- 
The changer is not responding.
- 
ch%d: warning, READ ELEMENT STATUS avail != count
- 
- 
ch%d: could not sense element address page
- 
- 
ch%d: could not sense capabilities page
- 
 
AUTHORS
 Jason R. Thorpe