MB> The file system mounting procedure simply is not used if the
 MB> device claims to be removable.  

   Then what does OS/2 do when you change a floppy?  HPOFS supports
removable media; how does it manage this?

 MB> LOCKDRV.FLT not only change the claim but also locks the media. 
 MB> It would be an easy -- and unwise -- hack to modify LOCKDRV.FLT 
 MB> so that it avoided actually locking the media, but continued to 
 MB> claim that it was not removable.

   Agreed.

 MB>   I suppose it is possible to allow dynamic locking and 
 MB> unlocking from a command line utility that communicates with 
 MB> the FLT, implementing a sort of mount/dismount command.

   I had thoughts along the same lines.  I just don't know enough to offer
any ideas on how...

   Side issue:  MO.SYS doesn't work here -- most versions report a sector
size of 65535, the newest version I have doesn't even see the drive.  This
prevents me from using HPOFS.  Browsing MO.SYS shows a reference to SCBs,
which SIT says my DPT doesn't support.  Does MO.SYS require SCB support?

Jeff

--- timEd/2 1.01