National Instruments NI-488.2 - Manual (Page 50)

Chapter 4 Developing Your NI-488.2 Application
© National Instruments Corporation 4-13 NI-488.2 User Manual
to get a pointer to the exported function, you just need to call
GetProcAddress passing the name of the function as a parameter. For
more information about the parameters to use when you invoke the
function, refer to the NI-488.2 online help. For instructions on accessing
the online help, refer to the
Using the NI-488.2 Documentation section in
About This Manual .
The functions such as ibfind , ibrdf , and ibwrtf all require an argument
that is a name. ibfind requires an interface or device name and ibrdf and
ibwrtf require a file name. Because Windows supports both ASCII (8-bit)
and Unicode (16-bit) characters, gpib-32.dll exports both ASCII and
Unicode versions of these functions. The ASCII versions are named
ibfindA , ibrdfA , and ibwrtfA . The Unicode versions are named
ibfindW , ibrdfW , and ibwrtfW . You can use either the Unicode or ASCII
versions of these functions with Windows.
In addition to pointers to the status variables and a handle to the loaded
gpib-32.dll , you must define the direct entry prototypes for the
functions you use in your application. For the prototypes for each function
exported by
gpib-32.dll , refer to the NI-488.2 online help. For
instructions on accessing the online help, refer to the Using the NI-488.2
Documentation section in About This Manual .
The direct entry sample programs illustrate how to use direct entry to
access
gpib-32.dll . For more information about direct entry, refer to the
online help for your development environment.
Directly Accessing the gpib-32.dll Exports
Make sure that the following lines are included at the beginning of your
C application:
#ifdef __cplusplus
extern "C"{
#endif
#include
#include "ni488.h"
#ifdef __cplusplus
}
#endif