Process Starter

  • Thread starter Thread starter L. L.
  • Start date Start date
L

L. L.

Hi All,

I know using Process class you can get the information of the current
processes
running on the current computer. Some processes are started by the user. And
some processes are started by other processes. My question is how do I know
the starter of a process? If process A is started by process B, how do I
know the information of the process B by querying process A?

Thanks,
Lenny
 
You don't.

--
HTH,
Kevin Spencer
..Net Developer
Microsoft MVP
Big things are made up
of lots of little things.
 
Kevin Spencer said:
You don't.

--
Click to expand...

Well you can. It's just not easy.

Here's how to do it in VB.


Declare Function CreateToolhelp32Snapshot _
Lib "KERNEL32.DLL" (ByVal dwFlags As Integer, _
ByVal th32ProcessID As Integer) As Integer
Declare Function Process32First Lib "KERNEL32.DLL" _
(ByVal hSnapshot As Integer, ByVal PE As Byte()) As Integer
Declare Function Process32Next Lib "KERNEL32.DLL" _
(ByVal hSnapshot As Integer, ByVal PE As Byte()) As Integer
Declare Function CloseHandle Lib "KERNEL32.DLL" _
(ByVal hObject As Integer) As Integer

Const TH32CS_SNAPPROCESS As Integer = 2
Const SIZEOF_PROCESSENTRY32 As Integer = 564
Const SIZE_OFFSET = 0
Const PROCESS_OFFSET = 8
Const PARENT_OFFSET = 24
'// typedef struct tagPROCESSENTRY32
'// {
'// DWORD dwSize;
'// DWORD cntUsage;
'// DWORD th32ProcessID;
'// DWORD th32DefaultHeapID;
'// DWORD th32ModuleID;
'// DWORD cntThreads;
'// DWORD th32ParentProcessID;
'// LONG pcPriClassBase;
'// DWORD dwFlags;
'// TCHAR szExeFile[MAX_PATH];
'// DWORD th32MemoryBase;
'// DWORD th32AccessKey;
'// } PROCESSENTRY32;

Function GetParentProcessID(ByVal id As Integer) As Integer
Dim b(564 - 1) As Byte
'write the size into the structure
BitConverter.GetBytes(SIZEOF_PROCESSENTRY32).CopyTo(b, SIZE_OFFSET)
Dim h As Integer = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0)
Try
Dim rv As Integer = Process32First(h, b)
If rv <> 1 Then
Throw New Exception("Could not enumerte processes.")
End If
While rv = 1
Dim pid As Integer = BitConverter.ToInt32(b, PROCESS_OFFSET)
Dim parent As Integer = BitConverter.ToInt32(b, PARENT_OFFSET)
If pid = id Then
Return parent
End If
rv = Process32Next(h, b)
End While
Finally
CloseHandle(h)
End Try

Return -1

End Function

Then to use it

'get the target process id (here the current process)
Dim pid As Integer =
GetParentProcessID(System.Diagnostics.Process.GetCurrentProcess.Id)

'get the parent process
Dim parent As System.Diagnostics.Process =
System.Diagnostics.Process.GetProcessById(pid)


This information is also available from the performance counters under
Process>[Instance]>Creating Process ID,
but you must enumerate the instances and identify the target process by
Process>[Instance]>ID Process
which is slow.

David
 
I stand corrected! Should have known better.

--
Kevin Spencer
..Net Developer
Microsoft MVP
Big things are made up
of lots of little things.

David Browne said:
Kevin Spencer said:
You don't.

--
Click to expand...

Well you can. It's just not easy.

Here's how to do it in VB.


Declare Function CreateToolhelp32Snapshot _
Lib "KERNEL32.DLL" (ByVal dwFlags As Integer, _
ByVal th32ProcessID As Integer) As Integer
Declare Function Process32First Lib "KERNEL32.DLL" _
(ByVal hSnapshot As Integer, ByVal PE As Byte()) As Integer
Declare Function Process32Next Lib "KERNEL32.DLL" _
(ByVal hSnapshot As Integer, ByVal PE As Byte()) As Integer
Declare Function CloseHandle Lib "KERNEL32.DLL" _
(ByVal hObject As Integer) As Integer

Const TH32CS_SNAPPROCESS As Integer = 2
Const SIZEOF_PROCESSENTRY32 As Integer = 564
Const SIZE_OFFSET = 0
Const PROCESS_OFFSET = 8
Const PARENT_OFFSET = 24
'// typedef struct tagPROCESSENTRY32
'// {
'// DWORD dwSize;
'// DWORD cntUsage;
'// DWORD th32ProcessID;
'// DWORD th32DefaultHeapID;
'// DWORD th32ModuleID;
'// DWORD cntThreads;
'// DWORD th32ParentProcessID;
'// LONG pcPriClassBase;
'// DWORD dwFlags;
'// TCHAR szExeFile[MAX_PATH];
'// DWORD th32MemoryBase;
'// DWORD th32AccessKey;
'// } PROCESSENTRY32;

Function GetParentProcessID(ByVal id As Integer) As Integer
Dim b(564 - 1) As Byte
'write the size into the structure
BitConverter.GetBytes(SIZEOF_PROCESSENTRY32).CopyTo(b, SIZE_OFFSET)
Dim h As Integer = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0)
Try
Dim rv As Integer = Process32First(h, b)
If rv <> 1 Then
Throw New Exception("Could not enumerte processes.")
End If
While rv = 1
Dim pid As Integer = BitConverter.ToInt32(b, PROCESS_OFFSET)
Dim parent As Integer = BitConverter.ToInt32(b, PARENT_OFFSET)
If pid = id Then
Return parent
End If
rv = Process32Next(h, b)
End While
Finally
CloseHandle(h)
End Try

Return -1

End Function

Then to use it

'get the target process id (here the current process)
Dim pid As Integer =
GetParentProcessID(System.Diagnostics.Process.GetCurrentProcess.Id)

'get the parent process
Dim parent As System.Diagnostics.Process =
System.Diagnostics.Process.GetProcessById(pid)


This information is also available from the performance counters under
Process>[Instance]>Creating Process ID,
but you must enumerate the instances and identify the target process by
Process>[Instance]>ID Process
which is slow.

David
Click to expand...
 
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