From: Park Heesob <phasis@...>
Date: 2003-03-18T22:51:40+09:00
Subject: Re: Gettig the pid of a process started with Win32_popen

Hi,
"Oliver Osterholz" <oliverosterholz@web.de> wrote in message
news:200303180820.h2I8Kt332142@mailgate5.cinetic.de...
> I have a problem with getting the pid of a program I opened with the
> popen2-method of the Win32_popen-Module. When I start my program with
> popen2 (on NT 4.0) I see two new processes in the process list. One is
> the program I started the other is a CMD.exe.
> Now I can communicate with the programm via pipes and it works fine. But
> now I want to kill the program again (with the kill-method) of the Module
> and I need the pid for it.
> I tried to get the pid with IO#pid (using one of the pipes) but it returns
> the pid of the CMD.exe.
> Does anybody know a way to get the right pid (or better to avoid to start
> the CMD.exe while starting my program)?

Your program is attached to CMD.exe.
If you want to kill your program, just kill CMD.exe.
So you don't need pid of your program.
If you really want to know pid of your program,
you can do it like following.

======================================
require 'win32_popen'
require 'Win32API'

RegCloseKey = Win32API.new("advapi32","RegCloseKey",['L'],'L')
RegOpenKeyEx =
Win32API.new("advapi32","RegOpenKeyEx",['L','P','L','L','P'],'L')
RegQueryValueEx =
Win32API.new("advapi32","RegQueryValueEx",['L','P','L','P','P','P'],'L')

INITIAL_SIZE        = 51200
EXTEND_SIZE         = 25600
REGKEY_PERF         = "SOFTWARE\\Microsoft\\Windows
NT\\CurrentVersion\\Perflib\\009"
REGSUBKEY_COUNTERS  = "Counters"
KEY_READ     =  0x20019;
ERROR_MORE_DATA     = 234
HKEY_LOCAL_MACHINE  = 0x80000002
HKEY_PERFORMANCE_DATA = 0x80000004

# return hash key : parent pids, value : array of  child pids
def getpids()
 result = Hash.new
 hKeyNames = "\0"*4
 rc = RegOpenKeyEx.Call(HKEY_LOCAL_MACHINE,REGKEY_PERF,0,KEY_READ,hKeyNames)
 hKeyNames = hKeyNames.unpack('L')[0]
 dwSize = "\0"*4
 rc = RegQueryValueEx.Call( hKeyNames,REGSUBKEY_COUNTERS,0,0,0,dwSize)
 dwSize2 = dwSize.unpack('L')[0]
 buf = "\0" * dwSize2
 rc = RegQueryValueEx.Call( hKeyNames,REGSUBKEY_COUNTERS,0,0,buf,dwSize)

 buf2 = Hash[*buf.split("\0")]

 proidx =  buf2.index("Process").to_i
 pididx = buf2.index("ID Process").to_i
 ppididx = buf2.index("Creating Process ID").to_i

 buf = "\0" * INITIAL_SIZE
 szSubKey = proidx.to_s
 dwSize = [INITIAL_SIZE]

 while true
  dwSize2 = dwSize.pack('L')
  rc = RegQueryValueEx.Call( HKEY_PERFORMANCE_DATA,szSubKey,0,0,buf,dwSize2)

  break if rc==0

  if rc == ERROR_MORE_DATA
   dwSize[0] += EXTEND_SIZE;
   buf = "\0" * dwSize[0]
  else
   exit
  end
 end

 pObj = buf[buf[24,4].unpack('L')[0] .. -1]

 pCounterDef = pObj[pObj[8,4].unpack('L')[0] .. -1]
 numCounters = pObj[32,4].unpack('L')[0]

 for i in 0 .. numCounters
  counterNameTitleIndex = pCounterDef[4,4].unpack('L')[0]
  if counterNameTitleIndex == pididx
   pidcounter = pCounterDef[36,4].unpack('L')[0]
  end
  if counterNameTitleIndex == ppididx
   ppidcounter = pCounterDef[36,4].unpack('L')[0]
  end
  pCounterDef = pCounterDef[40..-1]
 end

 dwNumTasks = pObj[40,4].unpack('L')[0]

 pInst = pObj[pObj[4,4].unpack('L')[0] .. -1]

 for i in 0 .. dwNumTasks
  pCounter = pInst[pInst[0,4].unpack('L')[0] .. -1]
  pid = pCounter[pidcounter,4].unpack('L')[0]
  ppid = pCounter[ppidcounter,4].unpack('L')[0]

  if ppid>0
    if result[ppid] == nil
   result[ppid] = [pid]
    else
     result[ppid].push(pid)
    end
  end
  pInst = pCounter[pCounter[0,4].unpack('L')[0] .. -1]
 end
 RegCloseKey.Call( hKeyNames )
 RegCloseKey.Call( HKEY_PERFORMANCE_DATA )
 result
end

fin,fout = IO.win32_popen2("yourprogram")
sleep 0.1 while getpids[fin.pid]==nil
pid = getpids[fin.pid][0]

==============================================

Park Heesob