OpenEuphoria

Re: DOS & Long File Names

• Posted by Jacques Deschenes <desja at GLOBETROTTER.QC.CA> Jul 26, 1998
• 443 views

At 16:14 26/07/98 -0700, you wrote:
>     I have very limited hard drive space.  I want to scan for Windows
>     programs.  I have a program that will let me find *.exe files, BUT I don't know
>     what the difference in the header between DOS executables and Windows
>     Executables.  (I want to get rid of any Windows programs floating around on my
>     computer.  There probably are some because I found one the other day.)  So
>     anybody know what the difference is?  Thanks for all your help.
>                            - Robert McDougal

here is a function that will check a file to determine if it is a windows
executable.

include file.e

constant signatures = { -- possible window file signatures
  "PE",-- window NT file
  "NE" -- window 3.x or later file
  }

-- this function return 1 if the file is a widowns executable (.DLL or .EXE)
-- return 0 if not a windows exec
-- return -1 if can't open it.
atom fh,ok
integer c,hdr
sequence FileId

  fh = open(FileName,"rb")
  if fh = -1 then return -1 end if
  FileId = getc(fh) & getc(fh)
  if compare(FileId,"MZ") != 0 then
    return 0  -- it's  not a DOS or windows executable
  end if

  ok = seek(fh,#18)
  c = getc(fh)+256*getc(fh)
  if c < #40 then
    close(fh)
    return 0  -- not a window file. (DOS executable)
  end if
  ok = seek(fh,#3C)
  hdr = getc(fh)+256*getc(fh) -- offset of new executable header
  ok = seek(fh,hdr)  -- window file header start here.
  FileId = getc(fh) & getc(fh)  -- new header signature
  close(fh)
  if find(FileId,signatures) then
    return 1   -- yes it is a windows executable file.
  else
    return 0  -- unkown file type.
  end if
------------------------------





Jacques Deschenes
Baie-Comeau, Quebec
Canada
desja at globetrotter.qc.ca