About This Manual

		This manual describes the LabVIEW programming objects that you use to
		call compiled code from text-based programming languages: the Call
		Library Function and the Code Interface Node. This manual includes
		reference information about libraries of functions, memory and file
		manipulation routines, and diagnostic routines that you can use with calls
		to external code.
Conventions
		The following conventions appear in this manual:
»		The » symbol leads you through nested menu items and dialog box options
		to a final action. The sequence File»Page Setup»Options directs you to
		pull down the File menu, select the Page Setup item, and select Options
		from the last dialog box.
		This icon denotes a tip, which alerts you to advisory information.
		This icon denotes a note, which alerts you to important information.
		This icon denotes a caution, which advises you of precautions to take to
		avoid injury, data loss, or a system crash.
bold		Bold text denotes items that you must select or click on in the software,
		such as menu items and dialog box options. Bold text also denotes
		parameter names.
italic		Italic text denotes variables, emphasis, a cross reference, or an introduction
		to a key concept. This font also denotes text that is a placeholder for a word
		or value that you must supply.
monospace		Text in this font denotes text or characters that you should enter from the
		keyboard, sections of code, programming examples, and syntax examples.
		This font is also used for the proper names of disk drives, paths, directories,
		programs, subprograms, subroutines, device names, functions, operations,
		variables, filenames and extensions, and code excerpts.
monospace bold		Bold text in this font denotes the messages and responses that the computer
		automatically prints to the screen. This font also emphasizes lines of code
		that are different from the other examples.

© National Instruments Corporation

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Using External Code in LabVIEW

About This Manual

monospace italic	Italic text in this font denotes text that is a placeholder for a word or value
	that you must supply.
Platform	Text in this font denotes a specific platform and indicates that the text
	following it applies only to that platform.

Related Documentation

The following document contains information that you might find helpful as you read this manual:

•LabVIEW User Manual

Sun users might also find the following document helpful:

•Sun Workshop CD-ROM, Sun Microsystems, Inc., U.S.A.

Linux users might also find the following document helpful:

•The GNU C Compiler Reference Manual, Free Software Foundation, 1989-2000.

Windows users might also find the following documents helpful:

•Microsoft Windows documentation set, Microsoft Corporation, Redmond, WA, 1992-1995

•Microsoft Windows Programmer’s Reference, Microsoft Corporation, Redmond, WA, 1992-1995

•Win32 Programmer’s Reference, Microsoft Corporation, Redmond, WA, 1992-1995

•Microsoft Visual C++ CD-ROM, Microsoft Corporation, Redmond, WA, 1997

Using External Code in LabVIEW

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Introduction

This manual discusses several methods in LabVIEW to call code written in other languages.

•Use platform-specific protocols.

•Use Call Library Function to call the following types of shared libraries:

–Dynamic Link Libraries (DLL) in Windows

–Code Fragments on the Macintosh

–Shared Libraries on UNIX

•Create a Code Interface Node to call code written specifically to link to VIs.

Also, to convert an instrument driver written in LabWindows/CVI you can select Tools»Instrumentation»Import CVI Instrument Driver and invoke the LabWindows/CVI Function Panel Converter. Refer to

LabVIEW Help for more information about this converter.

Calling Code in Various Platforms

This section describes the differences between running Windows and UNIX applications from within your VIs and running Macintosh applications from within your VIs.

(Windows and UNIX) Use the System Exec VI. Use the simple System Exec VI on the Functions»Communication palette to run a command line from your VI. The command line can include any parameters supported by

the application you want to launch.

If you can access the application through TCP/IP, you might be able to pass data or commands to the application. Refer to the documentation for the application for a description of its communication capability. If you are a LabVIEW user, refer to the Using LabVIEW with TCP/IP and UDP

Application Note for more information about techniques for using networking VIs to transfer information to other applications. You also can use many ActiveX LabVIEW tools to communicate with other applications.

© National Instruments Corporation

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Using External Code in LabVIEW