National Instruments 320685D-01 Using Windows SDK Functions for User Interface Capabilities, Using Windows SDK Functions to Create Multiple Threads , Automatic Loading of SDK Import Libraries

Chapter 3 Windows95/NT Compiler/Linker Issues

National Instruments Corporation 3-27 LabWindows/CVI Programmer Reference Manual

include files. For more information, refer to the Setting Up Include Paths for

LabWindows/CVI, ANSI C, and SDK Libraries section later in this chapter.

The number of SDK include files is very large. Normally, you have to include only

windows.h because it includes many, but not all, of the other include files. The inclusion of

windows.h along with its subsidiary include files significantly increases compilation time

and memory usage. WIN32_LEAN_AND_MEAN is a macro from Microsoft that speeds

compiling by eliminating the less commonly used portions of windows.h and its subsidiary

include files. By default, LabWindows/CVI adds /DWIN32_LEAN_AND_MEAN as a

compile-time definition when you create a new project. You can alter this setting by using the

Compiler Defines command in the Options menu of the Project window.

Using Windows SDK Functions for User Interface Capabilities

The LabWindows/CVI User Interface Library uses the Windows SDK. It isnot designed to

be used in programs that attempt to build other user interface objects at theSDK level. While

no specific restrictions exist on using SDK functions in LabWindows/CVI, National

Instruments recommends that you base your user interface either entirely on the

LabWindows/CVI User Interface Library or entirely on another user interface development

system.

Using Windows SDK Functions to Create Multiple Threads

Although you can use the Windows SDK Functions to create multiple threads in a

LabWindows/CVI program, the LabWindows/CVI dev el opm ent environment cannot handle

multiple threads. For instance, if your main program terminates without destroying the

threads, they do not terminate. Also, the LabWindows/CVI libraries are not multithread safe

when you run a program in the LabWindows/CVI development environment.

For information on using the LabWindows/CVI libraries in a multithreaded executable, refer

to the Multithreading and the LabWindows/CVI Libraries section earlier in this chapter.

Automatic Loading of SDK Import Libraries

All the SDK functions are in DLLs. LabWindows/CVI and the four external compilers each

come with a number of DLL import libraries for the SDK functions. Most of the commonly

used SDK functions are in the following three import libraries:

kernel32.lib

gdi32.lib

user32.lib

LabWindows/CVI for Windows95/NT automatically loads these three libraries when it starts

up and searches them to resolve references at link time. Thus, you do not have to include these

libraries in your project.