1.\" $NetBSD: ch.4,v 1.3 2001/09/12 18:19:16 wiz Exp $ 2.\" 3.Dd June 10, 1998 4.Dt CH 4 5.Os 6.Sh NAME 7.Nm ch 8.Nd SCSI media changer driver 9.Sh SYNOPSIS 10.Cd "ch* at scsibus? target ? lun ?" 11.Sh DESCRIPTION 12The 13.Nm 14driver is essentially an 15.Xr ioctl 2 16interface to a robot on a 17.Tn SCSI 18bus - a device that will change media (e.g. tapes, CD-ROMs, etc) 19in and out of drives for that media. 20The 21.Xr chio 1 22utility program uses this interface to manipulate such robots. 23.Sh FILES 24.Bl -tag -width /dev/rsdXXXXX -compact 25.It Pa /dev/ch Ns Ar u 26.Tn SCSI 27bus media changer unit 28.Ar u 29.El 30.Pa /usr/include/sys/chio.h 31.Sh DIAGNOSTICS 32.Bl -diag 33.It "ch%d: waiting %d seconds for changer to settle..." 34Some changers require a long time to settle out, 35to do tape inventory, for instance. 36.It "ch%d: offline" 37The changer is not responding. 38.It "ch%d: warning, READ ELEMENT STATUS avail != count" 39.It "ch%d: could not sense element address page" 40.It "ch%d: could not sense capabilities page" 41.El 42.Sh SEE ALSO 43.Xr chio 1 , 44.Xr ioctl 2 , 45.Xr cd 4 , 46.Xr intro 4 , 47.Xr scsi 4 , 48.Xr st 4 49.Sh AUTHORS 50.An Jason R. Thorpe 51