How to compile a 64-bit C DLL using MVS 2010 and run it in IDL

This Help article describes the steps to compile a 64-bit C DLL using Microsoft Visual Studio 2010 Express and how to call it in IDL afterwards.

Requirements:

- A 64-bit Windows machine

- A C compiler that supports 64-bit

- A 64-bit version of IDL

- The test will be run using a C code available in IDL distribution:

        C:\ProgramFiles\Exelis\IDLxx\external\dlm\testmodule.c

Before starting this tutorial please copy the testmodule.c file in addition to the testmodule.dlm_base file from the above directory into a test folder. For example

        C:\temp\test_dll_64bit\

Then rename testmodule.dlm_base to testmodule.dlm

Installation and configuration of the compiler

- Download a C compiler. In this example we will use the following  free C compiler: Microsoft Visual Studio 2010 Express

Note:  In order to have Microsoft Visual Studio 2010 Express compiling 64 bit application sit requires to install the following SDK library: Microsoft Windows SDK 7.1 & .NET Framework 3.5 SP1

- Install the C compiler (and the SDK  library mentioned above) on your 64-bit machine

 

Creation of the 64-bit C DLL

 

- Start the Microsoft SDK command line:

            Start > All Programs > Microsoft Windows SDK v7.1 > Windows SDK 7.1 Command Prompt

- Start the 64-bit IDL command line from the compiler prompt so the compiler path is automatically set.

        cd "C:\Program Files\Exelis\IDLxx\bin\bin.x86_64"

      idl.exe

 

- Build the 64-bit dll using the following IDL commands:

        c_dir='C:\temp\test_dll_64bit\'

        cd, c_dir

        make_dll, 'testmodule', 'IDL_Load', input_directory='c_dir', $

                OUTPUT_DIRECTORY=c_dir

 

Run the DLL from IDL

-  Paste the testmodule.dlm and the testmodule.dll created at the previous step from the test directory into the DLM default path. For example: 

               C:\Program Files\Exelis\IDLxx\bin\bin.x86_64

 

- Restart IDL using the IDL icon and run the commands:     

    DLM_REGISTER,'C:\Program Files\Exelis\IDLxx\bin\bin.x86_64\testmodule.dlm'

        print,testfun()

 

The output should be        

        % Loaded DLM: TESTMODULE

    % TESTFUN: This is from a loadable module function.

    TESTFUN

       

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HA reviewed on 3/25/2014 by DS