This program checks if a unit of a device is present.  It is
particularly useful for checking if a HD is accessible when booting,
although it works with any device (except those like console.device
which expects additional data).

Usage:  DevEx DEVICE/A,UNIT/O

DEVICE is the exec device name (e.g.  scsi.device), unit is the unit
of the device (which defaults to 0).  For SCSI host adapters the unit
number normally is identical to the SCSI unit, for IDE controllers 0
normally means the bus master and 1 the slave.

I wrote this program some time ago because my CyberSCSI host adapter
doesn't recognize my Syquest drive (being SCSI unit 1) right after
switching on when a cartridge is already inserted, i.e.  I cannot
access it during that session (strangely it works with my CD-ROM
drive).  So I inserted the following lines at the top of
s:startup-sequence:

makedir RAM:T
assign T: RAM:T  ;needed for "set ch `requestchoice ..."

DevEx >NIL: cybscsi.device 1
if WARN
	set ch `requestchoice "Just switched on ?" "Cannot find cybscsi.device unit 1"
"Reboot" "Continue"`
else
	set ch 0
endif

if not $ch eq 0
	HardReset
endif

Obviously this technique won't function if your boot device makes that
kind of trouble.  In that case I advise entering the boot menu by
pressing both mouse buttons, waiting until the HD has spinned up and
clicking on the "boot" gadget.

This program and its source code is public domain, i.e.  do with it
and its source code what you want.  As I don't expect money for it, I
don't guarantee for anything.

Contents:

SCOPTIONS          186 bytes    Options for SAS-C V6.58
DevEx              692 bytes    Executable, copy into C:
DevEx.c           1589 bytes    Source code
DevEx10a.readme   1966 bytes    This file

History:
	V1.0   21-Dec-97   Initial release

	V1.0a  21-Dec-97   Email address typo, sorry

 PERMSSN    UID  GID    PACKED    SIZE  RATIO     CRC       STAMP          NAME
---------- ----------- ------- ------- ------ ---------- ------------ -------------
[generic]                  507     692  73.3% -lh5- 4cf5 Dec 21  1997 DevEx
[generic]                  668    1589  42.0% -lh5- a893 Dec 21  1997 DevEx.c
[generic]                 1082    1966  55.0% -lh5- 6e49 Dec 21  1997 DevEx10a.readme
[generic]                  131     186  70.4% -lh5- 3191 Dec 21  1997 scoptions
---------- ----------- ------- ------- ------ ---------- ------------ -------------
 Total         4 files    2388    4433  53.9%            Dec 21  1997