.net – Correct name for non-COM, non-.NET DLL

comdllnetwindows

In the Windows world, what is the correct name for a good. old-fashioned C++ DLL with exported functions? Not a COM DLL, not a .NET DLL. The kind of DLL that we used to invoke by calling LoadLibrary() and GetProcAddress()?

I've always called them "flat DLLs" because the caller cannot instantiate objects from the DLL, but what is the correct name?

EDIT

Thanks for the answers.

Just "DLL" may be technically correct, but where I work everyone assumes that "DLL" means COM, or maybe at a push .NET, so I need a term that distinguishes exactly what I mean.

Best Answer

"Native" is probably the most common term, though "windows" or "console" are more technically correct, since these are the subsystems likely to be used (the "native" subsystem is something different). I have also heard "C DLL" used, implying the same as your use of "flat DLL".

A dynamic link library is a generic concept - a "Windows dynamic link library" is differentiated from *nix's equivalent, and also from managed libraries.

COM is little more than an encapsulation convention in this context - Windows DLLs can contain COM servers, as can portable executable (PE) files.

Related Solutions

C# – .NET String.Format() to add commas in thousands place for a number

String.Format("{0:n}", 1234);  // Output: 1,234.00
String.Format("{0:n0}", 9876); // No digits after the decimal point. Output: 9,876

.net – Identifying COM components in a .NET application

If you want to approach from the COM side, testing for COM objects in a DLL boils down to looking for an export named "DllGetClassObject". This is because an in-proc COM object is accessed by the COM runtime by calling DllGetClassObject() on that DLL.

You could do this from a batch file using DUMPBIN.EXE which comes with Visual Studio as follows:

dumpbin unknown.dll /exports | find "DllGetClassObject"

The above command line will produce one line of text if it is an unmanaged DLL that contains COM objects, or zero bytes of output otherwise.

You could do this programmatically by loading each DLL and try to do a GetProcAddress() on that entry point. Here is a tested and working C# command line program that uses this technique:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Runtime.InteropServices;

static class NativeStuff
{
    [DllImport("kernel32.dll")]
    public static extern IntPtr LoadLibrary(string dllToLoad);

    [DllImport("kernel32.dll")]
    public static extern IntPtr GetProcAddress(IntPtr hModule, string procedureName);

    [DllImport("kernel32.dll")]
    public static extern bool FreeLibrary(IntPtr hModule);
}

namespace IsComDLL
{
    class Program
    {
        static void Main(string[] args)
        {
            if ( (args.Length == 0 ) || String.IsNullOrEmpty( args[0] ) )
            {
                Console.WriteLine( "Give DLL name on command line" );
                Environment.Exit(255);
            }

            IntPtr pDll = NativeStuff.LoadLibrary(args[0]);
            if ( pDll == IntPtr.Zero )
            {
                Console.WriteLine( "DLL file {0} not found", args[0] );
                Environment.Exit(256);
            }

            IntPtr pFunction = NativeStuff.GetProcAddress(pDll, "DllGetClassObject");
            int exitValue = 0;
            if (pFunction == IntPtr.Zero)
            {
                Console.WriteLine("DLL file {0} does NOT contain COM objects", args[0]);
            }
            else
            {
                Console.WriteLine("DLL file {0} does contain COM objects", args[0]);
                exitValue = 1;
            }

            NativeStuff.FreeLibrary(pDll);

            Environment.Exit(exitValue);
        }
    }
}

Best Answer

Related Solutions

C# – .NET String.Format() to add commas in thousands place for a number

.net – Identifying COM components in a .NET application

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