National Instruments 320685D-01 Creating Executables that Use the LabWindows/CVI Libraries

Chapter 5 UNIX Compiler/Linker Issues

National Instruments Corporation 5-3 LabWindows/CVI Programmer Reference Manual

Creating Executables that Use the LabWindows/CVI Libraries

You can build executables that use the LabWindows/CVI libraries in two ways:

• You can build an executable in the LabWindows/CVI development environment by

selecting the Create Standalone Executable command in the Build menu of the Project

window. When you do so, LabWindows/CVI invokes the Sun Solaris linker (ld) to link

your programs to the Run-time Engine shared library.

• You can use an external compiler and linker to create an executable that uses the

Run-time Engine shared library. Use the Generate Makefile command in the Build menu

of the Project window to generate a UNIX makefile that corresponds to the currently

loaded project and libraries. The makefile invokes an external compiler to compile your

source files, and then it invokes the Sun Solaris linker (ld) to link the compiled files with

the Run-time Engine shared library.

You can use the following external ANSI C compilers to compile source files for linking with

the LabWindows/CVI Run-time Engine shared library.

• GNU C Compiler (gcc)

• Sun C Compiler (cc and acc)

Note Under Solaris 2.4, when linking the LabWindows/CVI Shared Library with

external ANSI C compiler, the compiler displays a warning that states the shared

library has an invalid type. You can ignore this warning.

When you build a project for execution in the LabWindows/CVI development environment,

LabWindows/CVI links your program to the static versions of the Sun Solaris libraries

(libc.a and libm.a). On the other hand, when you create a standalone executable in the

LabWindows/CVI development environment, LabWindows/CVI invokes the Sun Solaris link

editor (ld) to link your program to the shared versions of the libraries (libc.so and

libm.so). Similarly, when you generate a UNIX makefile by invoking the Generate

Makefile command from the Build Menu of the Project window, the makefile contains linker

commands to use the shared versions of the libraries.

Thus, when you run your programs as executables, you use a different version of the Sun

libraries (including the ANSI C library) than when you run them in the LabWindows/CVI

development environment. Your program might exhibit slightly different behavior as a

standalone executable than when run in the development environment.