Int 7A Fn 09  - Ibm 3270 Workstation Program Api - Session Services        [I]

   AH = 09h
   BX = 8020h (synchronous request)
   CX = 0000h
   DX = ID of session manager (SESSMGR)
   AL = service (see #3505)
   ES:DI -> control block

Return: ???

(Table 3505)
Values for service:
 01h   get session ID
 02h   get session info
 04h   dettach from session
 05h   attach to session
 06h   get list of windows available
 07h   get environment of window
 08h   get 'PIF' (program information file) info
 0Ah   get base window ID
 0Bh   get cursor info