/FHQ31: What do each of the four Protection Levels mean?/FB



In ``Change A Program'' or DVPMAN, you can set a program's protection
level.  Here are the meanings:



/CHLevel 0/CN means no protection at all.



/CHLevel 1/CN will keep a process from locking interrupts for too long if the
WD parameter is set correctly in QEMM, and your hardware supports it.



/CHLevel 2/CN will bring up an error if a process writes outside of the memory
that DESQview thinks the process owns. If the process attempts this,
DESQview will ask the user if the process should be aborted,
unprotected, or be allowed to continue (but remain protected).



/CHLevel 3/CN will keep a process from reading outside of its memory, with a
similar interface as Level 2.  It also grabs all interrupt vectors
and complains if the program points the vector outside of its memory
(including back at the original handler) and then calls it.  Level 3
will crash Borland's floating point libraries.



If a program crashes with Level 0 it will also crash with Level 3 set,
but you might find out about it a little sooner, and it may prevent the
system from being locked up.