Create a new application, or use existing application. A sample project 
application is provided as ioInterface.bpr.

If you wish to have a look at the sample main project, you can open it by clicking its name, 
ioBuild.bpr. This is the main project group, which includes both ioInterface.bpr and io.bpr. The 
I/O functions are stored in io.dll, which is in the project io.bpr. ioInterface.bpr is just any 
interface project (could be your own). In this case, it is used to test the functions included in 
io.dll. This will be the interface which calls the dll functions. If you wish to run this sample, 
make sure you create a directory named OBJs in your working directory. This is necessary 
otherwise the program will not compile but will return an "Error writing output file" exception. 
This is because I have set the Intermediate output option in the Directories/Conditionals tab in 
the Project|Options menu to OBJs. You can also alternatively create a batch file to do this, but 
make sure that it is the first project to be built and run. Do this by clicking the Build Sooner 
option.





If you wish to create your own interface application, follow the following steps:

In the Project Manager, from the project group, click Add Existing Project, and add the file 
io.bpr.

This file contains the io.dll file. Now, you should see the file io.cpp just below it.

**Copy io.h into the same folder in which you are working with.

Double-click io.dll in the project manager, and on the main menu, click Project|Options. Click 
Directories/Conditionals and verify that the Intermediate Output is set to OBJs and Conditional 
defines is set to _buildIOdll.

Double-click your own project name, and again click Project|Options. On the 
Directories/Conditionals tab, set Intermediate output to OBJs and Conditional defines to _NO_VCL. 
This will save all object files in the OBJs folder. If you were asked whether or not to create 
the folder, just click Yes. If you wish, you can now erase the directive #include <vcl.h> in your 
project.

Right-click your own project name, and choose Build Later. Build io.dll.

Right-click your own project, and choose Add. Change the Files of type to Library file (*.lib). 
Choose io.lib.

Add the #include "io.h" directive in your project.

You can now access all the interfacing functions packed with the DLL.