National Instruments 320685D-01 Include Files for the ANSI C Library and the LabWindows/CVI Libraries, Standard Input/Output Window, Resolving Callback References from .UIR Files

Chapter 3 Windows95/NT Compiler/Linker Issues

LabWindows/CVI Programmer Reference Manual 3-10

National Instruments Corporation

If you use an external compiler that requires a WinMain entry point, the following optional

library allows you to define only main in your program.

cviwmain.lib /* contains a WinMain() function which */

/* calls main() */

Include Files for the ANSI C Library and the LabWindows/CVI Libraries

The cvirt.lib import library contains symbols for all the LabWindows/CVI libraries,

except the ANSI C standard library. When you create an executable or DLL in an external

compiler, you use the compiler’s own ANSI C standard library. Because of this, you must use

the external compiler’s include files for the ANSI C library when compiling source files.

Although the include files for the other LabWindows/CVI libraries are in the cvi\include

directory, the LabWindows/CVI ANSI C include files are in the cvi\include\ansi

directory. Thus, you can specify cvi\include as an include path in your external compiler

while at the same time using the external compiler’s version of the ANSI C include files.

Note Use the external compiler’s ANSI C include files only when you compile a source

file that you intend to link using the external compiler. If you intend to link the file

in LabWindows/CVI, use the LabWindows/CVI ANSI C include files. This is true

regardless of which compiler you use to compile the source file.

For more information, refer to the Setting Up Include Paths for LabWindows/CVI, ANSI C,

and SDK Libraries section later in this chapter.

Standard Input/Output Window

One effect of using the external compiler’s ANSI C standard library is that the printf and

scanf functions do not use the LabWindows/CVI Standard Input/Output window. If you

want to use printf and scanf, you must create a console application, which is called a

character-mode executable in Watcom.

You can continue to use the LabWindows/CVI Standard Input/Output Window by calling the

FmtOut and ScanIn functions in the Formatting and I/O library.

Resolving Callback References from .UIR Files

When you link your program in LabWindows/CVI, LabWindows/CVI keeps a table of the

non-static functions that are in your project. When your program calls LoadPanel or

LoadMenuBar, the LabWindows/CVI User Interface Library uses this table to find the

callback functions associated with the objects you load from the user interface resource

(.uir) file. This is true whether you run your program in the LabW indo ws/CVI de vel opment

environment or as a standalone executable.