From: ptkwt@... (Phil Tomson)
Date: 2003-12-31T12:36:48+09:00
Subject: Re: Win32API question: accessing a PBOOL

In article <c68ca8f2.0312301225.64aabd7a@posting.google.com>,
Phil Tomson <intc_ctor@yahoo.com> wrote:
>I'm trying to call:
>(from MSDN info):
>" BOOL IsWow64Process(
>   HANDLE hProcess,
>   PBOOL Wow64Process
> );
>
>Parameters
>
>hProcess
>    [in] Handle to a process.
>Wow64Process
>    [out] Pointer to a value that is set to TRUE if the process is
>running under WOW64. Otherwise, the value is set to FALSE.
>
>Return Values
>
>If the function succeeds, the return value is a nonzero value.
>
>If the function fails, the return value is zero."
>
>I can see that return value is 1 meaning that the call succeeded, but
>I can't seem to get anything out of the Wow64Process parameter.
>
>Here's the code snippet:
>
>#########Should work on WinXP, other Wins will skip the relevant code
>######
>require 'Win32API'
>begin
>  #only works on XP which is why we rescue:
>  Is64bit  = Win32API.new("kernel32","IsWow64Process",['L','P'],'L')
>rescue 
>  puts "you're not on XP"
>  Is64bit = nil
>  isXP    = false
>else
>  puts "you're on XP, but is it 64 bit?"
>  isXP    = true
>end
>#Now try to see if we're running on WinXP 64bit edition:
>  is64 = "f" #string to pass into the Wow64Process param
>  if isXP
>    puts "Possibly 64bit.  Checking..."
>    result = Is64bit.call(GetCurrentProcess.call(),is64)
>    #is64 should be false on WinXP and true on WinXP-64bit#
>    puts "result is: #{result}, is64 is #{is64.unpack("L")}"

Turns out I needed:
     puts "result is: #{result}, is64 is #{is64.unpack("c")[0]}"

>  else
>    puts "Not 64bit"
>  end
>#########end########
>


That works.

Phil