Int 68 Fn 06  - Appc/pc - Change Number Of Sessions                        [N]

   AH = 06h
   DS:DX -> control block (see below)

Return: control block updated

Format of control block:
Offset Size    Description
 00h 12 BYTEs  reserved
 0Ch   WORD    1500h (verb "Change Number of Sessions")
 0Eh  6 BYTEs  00h
 14h   WORD    (big-endian) primary return code (see AH=02h)
 16h   DWORD   (big-endian) secondary return code (see below, AH=01h/SF=1B00h)
 1Ah  8 BYTEs  (big-endian) logical unit ID
 22h  8 BYTEs  blanks
 2Ah  8 BYTEs  (big-endian) partner logical unit name
 32h  8 BYTEs  (big-endian) mode name
 3Ah   BYTE    bit 7: use MODE_NAME_SELECT_ALL rather than MODE_NAME
       bit 6: set negotiable values
 3Bh   BYTE    partner logical unit mode session limit
 3Ch   BYTE    minimum CONWINNERS_SOURCE
 3Dh   BYTE    maximum CONWINNERS_TARGET
 3Eh   BYTE    automatic activation
 3Fh   BYTE    00h
 40h   BYTE    bit 7: drain target
       bit 6: drain source
       bit 5: target responsible, not source

Values for secondary return code (see also AH=01h/SF=1B00h):
 0000h accepted
 0001h negotiated
 0003h bad logical unit ID
 0004h allocation failure, no retry
 0005h allocation failure, retry
 0151h can't raise limits
 0153h all modes must reset
 0154h bad SNASVCMG limits
 0155h minimum greater than total
 0156h mode closed (primary return code = 1)
   CNOS mode closed (primary return code = 18h)
 0157h bad mode name (primary return code = 1)
   CNOS bad mode name (primary return code = 18h)
 0159h reset SNA drains
 015Ah single not SRC response
 015Bh bad partner logical unit
 015Ch exceeds maximum allowed
 015Dh change SRC drains
 015Eh logical unit detached
 015Fh CNOS command race reject