Open a file in Visual Studio at a specific line number

I have a utility (grep) that gives me a list of filenames and a line numbers. After I have determined that devenv is the correct program to open a file, I would like to ensure that it is opened at the indicated line number. In emacs, this would be:

emacs +140 filename.c

I have found nothing like this for Visual Studio (devenv). The closest I have found is:

devenv /Command "Edit.Goto 140" filename.c

However, this makes a separate instance of devenv for each such file. I would rather have something that uses an existing instance.

These variations re-use an existing devenv, but don't go to the indicated line:

devenv /Command "Edit.Goto 140" /Edit filename.c
devenv /Command  /Edit filename.c "Edit.Goto 140"

I thought that using multiple "/Command" arguments might do it, but I probably don't have the right one because I either get errors or no response at all (other than opening an empty devenv).

I could write a special macro for devenv, but I would like this utility to be used by others that don't have that macro. And I'm not clear on how to invoke that macro with the "/Command" option.

Any ideas?

Well, it doesn't appear that there is a way to do this as I wanted. Since it looks like I'll need to have dedicated code to start up Visual Studio, I've decided to use EnvDTE as shown below. Hopefully this will help somebody else.

#include "stdafx.h"

//-----------------------------------------------------------------------
// This code is blatently stolen from http://benbuck.com/archives/13
//
// This is from the blog of somebody called "BenBuck" for which there
// seems to be no information.
//-----------------------------------------------------------------------

// import EnvDTE
#pragma warning(disable : 4278)
#pragma warning(disable : 4146)
#import "libid:80cc9f66-e7d8-4ddd-85b