HelpPC 2.10 Quick Reference Utility Copyright 1991 David Jurgens

           INT 2F,0 - DOS Multiplex Interrupt - Get Installed State

       AL = 00
       AH = 00  DOS 2.x PRINT.COM (undocumented, see note below)
            01  PRINT  (undocumented behavior also, see note below)
            05  Critical error handler (undocumented DOS 3.0+)
            06  ASSIGN  (see note)
            08  DRIVER.SYS (undocumented DOS 3.2+)
            10  SHARE
            11  Redirector/IFS is resident
            12  MultiDOS is resident
            13  Swap 13h and 19h
            14  NLSFUNC
            15  GRAPHICS.COM (see note below)
                MS CD-ROM extension (MSCDEX) (see note below)
            16  Windows 386
            17  DOS shell
            19  SHELLB.COM (DOS 4.0 only)
            1A  ANSI.SYS (DOS 4.0+)
            1B  XMA2EMS.SYS
            40  OS/2 compatibility box
            43  Himem XMS driver
            7A  Novell Netware IPX
            AD  DISPLAY.SYS internal (DOS 3.3+)
            AE  DOS installable command extension (DOS 3.3+)
            B0  GRAFTABL.COM (DOS 3.3+)
            B4  IBM 3270 emulation
            B7  APPEND  (DOS 3.3+)
            B8  LAN existence
            B9  LAN RECEIVER.COM
            BF  LAN REDIRIFS.EXE
            C0-FF reserved for user applications

       on return:
       AL = 00  not installed, ok to install
          = 01  not installed, do NOT install
          = FF  installed

       - the installed test for append returns non-zero if installed;
         zero if not installed
       - AH = 00 and 01 are used by DOS 2.x PRINT.COM and is not a check
         for installed state, see BIBLIO reference to "Undocumented DOS"
       - ASSIGN returns non-zero if installed
       - installation checks with AH=15 do not follow the standard format;
       - see  Bibliography reference to "Undocumented DOS"

Esc or Alt-X to exit int 2f,0 Home/PgUp/PgDn/End ←↑↓→
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