<p>Is it possible to break at runtime when a particular file has been modified?  </p>

<p>ie. monitor the file and break into a debugger once a change has been made to it.</p>

<p>This is for a windows app...is this possible in visual studio or windbg?</p>

<p>edit:  i should have mentioned that this is for a Win32 app..</p>

Assuming this is .NET, the System.IO.
FileSystemWatcher
class is what you need.
```
```
FileSystemWatcher watcher = new FileSystemWatcher("c:filename.txt");
watcher.Changed += new FileSystemEventHandler(watcher_Changed);
// 
void watcher_Changed(object sender, FileSystemEventArgs e)
{
    // put a breakpoint here
}
```
```