ERRORBASE()
 Source of the most-recent DOS error
------------------------------------------------------------------------------
 Syntax

     ERRORBASE() --> nErrorCode

     Warning!  This function requires DOS 3.1 or higher.

 Returns

     ERRORBASE() returns a numeric code that provides additional information
     about the cause of the error.  These codes and their definitions are in
     the table below:

     Table 12-3: Causes for DOS Errors
     ------------------------------------------------------------------------
     Code      Definition
     ------------------------------------------------------------------------
     1         Insufficient memory
     2         Access temporarily denied
     3         No access for this user
     4         Internal error, system software
     5         Hardware error
     6         Error in system software
     7         Error in applications program
     8         File not found
     9         Wrong file format or type
     10        File is protected
     11        Incorrect medium in drive
     12        Other error
     ------------------------------------------------------------------------

 Description

     If an error is detected with ERRORCODE(), use ERRORBASE() for more
     information about the cause of the error, from within the data returned
     by DOS.

 Example

     Determine the cause for an error:

     nCause  :=  ERRORBASE()
     IF nCause = 3
        ? "Access denied!"
     ENDIF