7)  DRIVPARM /c

    Syntax:  DRIVPARM /d:number [/c] [/f:factor] [/h:heads] [/i] [/n]
             [/s:sectors] [/t:tracks]

    /d:n   refers to the drive NUMBER (0=A:, 1=B:, 2=C:, etc...) of the drive
           whose parameters you are changing (in your case, it would be 2 for
           B:).

    /c     is the switch I was referring to for change line support.  IF YOU
           INCLUDE /c, YOU ARE TELLING DOS THAT YOUR COMPUTER *CAN* TELL
           WHETHER THE DRIVE DOOR HAS BEEN OPENED SINCE THE LAST ACCESS.

    /i     specifies an electronically-compatible 3.5 inch floppy disk-drive.
           You should use it if your computer's ROM BIOS does NOT support 3.5
           floppy diskette drives.

    /n     specifies a NON-removable block device

    The other parms are similar to DRIVER.SYS

                              IBM Technical Publication Information
                              forwarded by Andrew Barnhardt

    The '/C' switch doesn't actually check to see if the drive -door-
    has been opened or not, but it does make another check to see if
    the disk in there now is different from the one when the drive was
    last accessed.  I have to use that switch with my 5 1/4 floppy
    because it's an older drive working with a new motherboard (at
    least that's the explanation I've heard).

                              Andrew Barnhardt

    Does DRIVPARM return an errorlevel, or give a warning message?

                              Gary Cooper

    No, not that I'm aware of.  You insert the drivparm command in
    your CONFIG.SYS file.  Just DRIVPARM=xx xx ...

                              Andrew Barnhardt
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8)  IF EXIST

    IE: IF EXIST EMMXXXX0 GOTO APPLICATION

    This is a handy quirk of DOS - installable drivers are seen as files
    in all directories.  You can use the if exist test to either test for
    the existence of a directory, with "if exist <dirname>\nul", (which
    fails if the directory does not exist because the nul device is not
    found,) or to test whether a driver is loaded.

    Caveats:  you need to know the name of the directory or the driver
    whose existance you are testing, and this is MS/DOS specific - it
    doesn't work on network drives, and may not work under DR-DOS.

                              Gary Marden

    This works definitely under DRDOS:

              DR DOS Version 6.0
              Copyright (c) 1976,1982,1988,1990,1991 Digital Research Inc.
              Alle Rechte vorbehalten.

              C:\>if exist emmxxxx0 echo ja
              ja

                              Wolfram Serber

    Where did you learn the "EMMXXXX0" name from?

    Instead of typing MEM /C, type MEM /D for the "debug" listing.
    That should give the names you're looking for.

                              Erik Ratcliffe

    The trouble is, EXISTS returns TRUE for COM3/4 and LPT2/3 even
    though the hardware does not exist.

                              Rudy Lacchin

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