Underground And Other Stuff

Where is a special-purpose FIND program that displays the location of files that match a search pattern. The default behavior of Where is to search the current directory and the locations specified by the PATH environment variable--in order. So if you enter the command "where foobie.exe", the program will perform the same search that Windows does when it's searching for a command that you enter. You very quickly learn which version of foobie.exe is being found and executed by Windows.

There are command line options that allow you to recursively search directories in the same way that FIND does. You can also tell the tool to display all of the matching files along the PATH search. Enter "where /?" to get a full list of command line options.

Where.exe is located at {Visual Studio Directory}\Common7\Tools\Bin\Where.exe. If you want to make it available from the command line, you'll need to put that location in your PATH environment variable, or copy the program to your utilities directory if you have one. Of course, you then have to worry about which version of Where is being executed. "where where.exe".

Error Lookup

I spend a lot of time working with platform invoke, calling Windows API functions. In case you forgot, Windows API functions typically indicate success or failure in a Boolean return value, and provide more information by calling SetLastError to set the global error code. .NET programs can access that error code by calling Marshal.GetLastWin32Error.

Figuring out what those error codes mean so that you can provide meaningful information in a .NET exception is the hard part. You can look up the code in the Platform SDK help file WinError.h, but that gets tedious. A better option is the Error Lookup utility, located at {Visual Studio Directory}\Common7\Tools\errlook.exe. Just copy or type the error code and click the Lookup button, or drag-and-drop an error code from Visual Studio Debugger. The program looks up the error by calling the Windows API FormatMessage function, and then displays it.

A link to Error Lookup was included on the Visual Studio .NET Tools menu for Visual Studio .NET 2003, but the link doesn't exist in Visual Studio .NET 2005. You'll have to create your own shortcut if you want to use the program.

Other Tools

There are several others that you might find useful, and of course there are the many documented command-line tools that you can find in the .NET SDK and in other places. Spend some time exploring the directories I mentioned above and other Visual Studio locations. You'll almost certainly find useful tools that you didn't know existed.