INT 21 - DOS 3+ - GET EXTENDED ERROR INFORMATION
        AH = 59h
        BX = 0000h
Return: AX = extended error code (see below)
        BH = error class (see below)
        BL = recommended action (see below)
        CH = error locus (see below)
        ES:DI may be pointer (see error code list below)
        CL, DX, SI, BP, and DS destroyed
Notes:  functions available under DOS 2.x map the true DOS 3+ error code into
          one supported under DOS 2.x
        you should call this function to retrieve the true error code when an
          FCB or DOS 2.x call returns an error
        under DR-DOS 5.0, this function does not use any of the DOS-internal
          stacks and may thus be called at any time
SeeAlso: AH=59h/BX=0001h,AX=5D0Ah,INT 2F/AX=122Dh

Values for extended error code:
 00h (0)   no error
 01h (1)   function number invalid
 02h (2)   file not found
 03h (3)   path not found
 04h (4)   too many open files (no handles available)
 05h (5)   access denied
 06h (6)   invalid handle
 07h (7)   memory control block destroyed
 08h (8)   insufficient memory
 09h (9)   memory block address invalid
 0Ah (10)  environment invalid (usually >32K in length)
 0Bh (11)  format invalid
 0Ch (12)  access code invalid
 0Dh (13)  data invalid
 0Eh (14)  reserved
 0Fh (15)  invalid drive
 10h (16)  attempted to remove current directory
 11h (17)  not same device
 12h (18)  no more files
---DOS 3+---
 13h (19)  disk write-protected
 14h (20)  unknown unit
 15h (21)  drive not ready
 16h (22)  unknown command
 17h (23)  data error (CRC)
 18h (24)  bad request structure length
 19h (25)  seek error
 1Ah (26)  unknown media type (non-DOS disk)
 1Bh (27)  sector not found
 1Ch (28)  printer out of paper
 1Dh (29)  write fault
 1Eh (30)  read fault
 1Fh (31)  general failure
 20h (32)  sharing violation
 21h (33)  lock violation
 22h (34)  disk change invalid
        ES:DI -> ASCIZ volume label of required disk
 23h (35)  FCB unavailable
 24h (36)  sharing buffer overflow
 25h (37)  (DOS 4+) code page mismatch
 26h (38)  (DOS 4+) cannot complete file operation (out of input)
 27h (39)  (DOS 4+) insufficient disk space
 28h-31h   reserved
 32h (50)  network request not supported
 33h (51)  remote computer not listening
 34h (52)  duplicate name on network
 35h (53)  network name not found
 36h (54)  network busy
 37h (55)  network device no longer exists
 38h (56)  network BIOS command limit exceeded
 39h (57)  network adapter hardware error
 3Ah (58)  incorrect response from network
 3Bh (59)  unexpected network error
 3Ch (60)  incompatible remote adapter
 3Dh (61)  print queue full
 3Eh (62)  queue not full
 3Fh (63)  not enough space to print file
 40h (64)  network name was deleted
 41h (65)  network: Access denied
 42h (66)  network device type incorrect
 43h (67)  network name not found
 44h (68)  network name limit exceeded
 45h (69)  network BIOS session limit exceeded
 46h (70)  temporarily paused
 47h (71)  network request not accepted
 48h (72)  network print/disk redirection paused
 49h (73)  network software not installed
           (LANtastic) invalid network version
 4Ah (74)  unexpected adapter close
           (LANtastic) account expired
 4Bh (75)  (LANtastic) password expired
 4Ch (76)  (LANtastic) login attempt invalid at this time
 4Dh (77)  (LANtastic v3+) disk limit exceeded on network node
 4Eh (78)  (LANtastic v3+) not logged in to network node
 4Fh (79)  reserved
 50h (80)  file exists
 51h (81)  reserved
 52h (82)  cannot make directory
 53h (83)  fail on INT 24h
 54h (84)  (DOS 3.3+) too many redirections
 55h (85)  (DOS 3.3+) duplicate redirection
 56h (86)  (DOS 3.3+) invalid password
 57h (87)  (DOS 3.3+) invalid parameter
 58h (88)  (DOS 3.3+) network write fault
 59h (89)  (DOS 4+) function not supported on network
 5Ah (90)  (DOS 4+) required system component not installed
 64h (100) (MSCDEX) unknown error
 65h (101) (MSCDEX) not ready
 66h (102) (MSCDEX) EMS memory no longer valid
 67h (103) (MSCDEX) not High Sierra or ISO-9660 format
 68h (104) (MSCDEX) door open

Values for Error Class:
   1 01h    out of resource (storage space or I/O channels)
   2 02h    temporary situation (file or record lock)
   3 03h    authorization (denied access)
   4 04h    internal (system software bug)
   5 05h    hardware failure
   6 06h    system failure (configuration file missing or incorrect)
   7 07h    application program error
   8 08h    not found
   9 09h    bad format
  10 0Ah    locked
  11 0Bh    media error
  12 0Ch    already exists
  13 0Dh    unknown

Values for Suggested Action:
   1 01h    retry
   2 02h    delayed retry
   3 03h    prompt user to reenter input
   4 04h    abort after cleanup
   5 05h    immediate abort
   6 06h    ignore
   7 07h    retry after user intervention

Values for Error Locus:
   1 01h    unknown or not appropriate
   2 02h    block device (disk error)
   3 03h    network related
   4 04h    serial device (timeout)
   5 05h    memory related

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