'from: Martin Kiewitz

PRINT DOS_GetOSSystemName

FUNCTION DOS_GetOSSystemName() as STRING
  local Version?,Release?

  Version?=0
  Release?=0
  'OS/2 -------------
  ! PUSH AX
  ! PUSH BX
  ! PUSH CX
  ! PUSH DX
  ! MOV AX, &h4010
  ! INT &h2F
  ! MOV Version?, AL
  ! MOV Release?, AH
  IF Release?<>&h40 AND Version?<>&h10 THEN
    OS$="OS/2"
    ! MOV Version?, BL
    ! MOV Release?, BH
  END IF
  IF Release?=0 AND Version?=0 THEN
    OS$="OS/2 Warp"
    Version?=3
    Release?=0
  END IF
  ! POP DX
  ! POP CX
  ! POP BX
  ! POP AX

  ' DR-DOS -----
  ! PUSH AX
  ! PUSH BX
  ! PUSH CX
  ! PUSH DX
  ! MOV AX, &h3000
  ! STC
  ! INT &h21
  ! JC NixDR
  ! MOV Version?, AL
  ! MOV Release?, AH
  OS$="DR-DOS"
  NixDR:
  ! POP DX
  ! POP CX
  ! POP BX
  ! POP AX

  'Novell DOS
  IF OS$="DR-DOS" AND ENVIRON$("OS")="NWDOS" THEN OS$="Novell DOS":Version?=7:Release?=0

  IF OS$="" then
     ' MS-DOS -------------
     ! push ax
     ! push bx
     ! push cx
     ! push dx
     ! mov ax,&H3306
     ! int &H21
     ! mov Version?,bl
     ! mov Release?,bh
     ! pop dx
     ! pop cx
     ! pop bx
     ! pop ax
     OS$="MS-DOS"
  end if
  FUNCTION = OS$+" "+REMOVE$(STR$(Version?)+"."+STR$(Release?)," ")
END FUNCTION