A sample DLL

The DLL we will build will consist of a single source file "example_dll.cpp":

#include <stdio.h>
#include "example_dll.h"

__stdcall void hello(const char *s)
{
        printf("Hello %s\n", s);
}
int Double(int x)
{
        return 2 * x;
}
void CppFunc(void)
{
        puts("CppFunc");
}
void MyClass::func(void)
{
        puts("MyClass.func()");
}

The following header "example_dll.h" declares the interface of the DLL, and is used both when building the DLL and when building an executable that uses the DLL:

<pre>

1. ifndef EXAMPLE_DLL_H

This page is about how to "call into" an existing DLL, using your mingw program. for information on creating your own DLL library, see DLL.

Usually (read: for all DLLs created with MinGW and also a few others) MinGW links fine against a DLL. No special import library is necessary (see sampleDLL).

However there are situations when it won't. Then one needs a so-called import library to help the linker. The rest of this page gives hints as to how to create such import libraries when there is only the DLL available.