Procedure Vreset(var stat: VI_status_type);
   EXTERNAL;
{*USER*
 
VRESET is used to reintialize the VIEWPORT interface.  The VIEWPORT interface
uses a global data area that is reserved for its exclusive use.  This area,
which is not directly accesible by the user, remains transparent to the
user.  However, it must be intialized for use by the VIEWPORT interface.
This was already done once with VINIT.  Thereafter, we must use VRESET
to reinitialize the interface.
 
Since all connected job and cache info is lost, we will
disconnect from any connected jobs prior to the reinitialization.
 
REMEMBER, VINIT must be called the first time to initialize cache and
other internal variables, while VRESET is called any subsequent times
that a "re-initialization" is desired.
 
*ERROR CODES*
 
VI_SUCCESS - Re-Initialization is complete.
 
}