INT 21,59 - Get Extended Error Information (DOS 3.0+)

AH = 59h

BX = 00 for versions 3.0, 3.1, 3.2

on return:

AX = extended error code (see ~DOS ERROR CODES~)

= 0 if no error

BH = error class

BL = suggested action

CH = locus

- may be called after any ~INT 21~ function or from

~INT 24~ when an error is returned

- must be called immediately after the error occurs

- registers CX, DX, DI, SI, BP, DS and ES are destroyed