National Instruments DeviceNet NI-DNET, Руководство пользователя

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Chapter 3 Developing Your Application
NI-DNET User Manual 3-4 ni.com
For C applications (files with
.c
extension), include the header file by
adding a
#include
to the beginning of your code, like this:
#include "nidnet.h"
For C++ applications (files with
.cpp
extension), define
_cplusplus
before including the header, such as:
#define _cplusplus
#include "nidnet.h"
The
_cplusplus
define enables the transition from C++ to the C language
NI-DNET functions.
The reference for each NI-DNET function is provided in the NI-DNET
Programmer Reference Manual , which you can open from Start»All
Programs»National Instruments»NI-DNET .
You can find examples for Visual C++ in the
examples
subfolder of the
Borland C
folder. Each example is in a separate folder. A
.c
file with the
same name as the example contains a description the example in comments
at the top of the code.
Other Programming Languages
You can directly access NI-DNET from any programming environment
that allows you to request addresses of functions that a dynamic link library
(DLL) exports. The functions used to access a DLL in this manner are
provided by the Microsoft Win32 functions of Windows. Using these
Microsoft Win32 functions to access a DLL is often referred to as direct
entry. To use direct entry with NI-DNET, complete the following steps:
1. Load the NI-DNET DLL,
nican.dll
.
The following C language code fragment illustrates how to call the
Win32
LoadLibrary
function and check for an error.
#include <windows.h>
#include "nidnet.h"
HINSTANCE NidnetLib = NULL;
NidnetLib=LoadLibrary("nican.dll");
if (NidnetLib == NULL) {
return FALSE; /*Error*/
}