National Instruments 320685D-01 Creating Executables in LabWindows/CVI, Creating DLLs in LabWindows/CVI

Chapter 3 Windows95/NT Compiler/Linker Issues

LabWindows/CVI Programmer Reference Manual 3-20

National Instruments Corporation

Creating Executables in LabWindows/CVI

You can create true 32-bit Windows ex ecutables in LabW indows/CVI for W indo ws95/NT. In

LabWindows/CVI for Windows3.1, you run standalone programs using a special executable

file that contains the LabWindows/CVI run-time libraries. If you run more than one program

at a time, Windows 3.1 loads extra copies of this special executable into memory. Under

Windows95/NT, the LabWindows/CVI run-time libraries come in DLL form. Standalone

executables you create in LabWindows/CVI and executables you create in external compilers

use the same DLLs. If you run more than one program at a time, Windows 95/NT loads only

one copy of the DLL.

To create a standalone executable, you must first select Standalone Executable from the

submenu attached to the Target command in the Build menu of the Project window. When

you select Standalone Executable, the Create Standalone Executable command appears

below the Target command in the Build menu. The Create Standalone Executable

command under Windows95/NT is the same as under Windows 3.1, except that you also can

specify version information to include in the executable in the form of a standard Windows

version resource.

Creating DLLs in LabWindows/CVI

In LabWindows/CVI for Windows95/NT, you can create 32-bit DLLs. Along with each

DLL, LabWindows/CVI creates a DLL import library for your compatible compiler. You can

choose to create DLL import libraries compatible with all four external compilers.

You must have a separate project for each DLL you want to create. Select Dynamic Link

Library from the submenu attached to the Target command in the Build menu of the Project

window. When you select Dynamic Link Library, the Create Dynamic Link Library

command appears below the Target command in the Build menu. Refer to Chapter 3, Project

Window, in the LabWindows/CVI User Manual, for detailed information on the Create

Dynamic Link Library command.

You can debug the DLLs you create in LabWindows/CVI. Refer to the DLL Debugging

(Windows 95/NT Only) section in Chapter 3, Project Window, of the LabWindows/CVI

User Manual, for more information.

If you have to perform special processing in your DLL import library, you can customize it.

Instead of generating a .lib file, you can generate a .c file that contains source code. If you

do this, however, you can export only functions from the DLL, not variables.