Data types

[jom20]

Hi,

Its a really stupid question however, can anyone explain this line of code to me please

#define S_IDLE ((uint16) 0)

I know its defining a constant call S_IDLE, and I know its an unsigned short.

In java when its written like that I think it means casting it to a unsigned short, but I am not sure if this is the same for C++.

and also this line

typedef struct


Thanks
Trisha

[Andreas Masur]

Originally posted by jom20
In java when its written like that I think it means casting it to a unsigned short, but I am not sure if this is the same for C++.

Yes...this is an old-style C cast...

Originally posted by jom20
and also this line

typedef struct

Well...what is your question with that line? I mean the line is basically incomplete... :cool:

[jom20]

The block code is:

typedef struct
{
uint16 uiCom;
boolean block;
}TxAdmin


I dont understand what this means.

[jom20]

In visual C++ I need to include some header file from the software for my chip. I know the directory where they are stored the problem is that when I type for example #include "app.h" I get an error saying that it cannot find the directory. How can I overcome this. DO I need to copy and paste the codes from these header files into one that I create myself.

Or do I need to move the directory.

Thanks

[HeartBreakKid]

You need to specify the include directory for your project:

1. Open your project in Solution Explorer (from VS.NET, View->Solution Explorer)

2. Right click on your project name, and go to properties.


3. On the left hand side (the tree view) select Configuration Properties->C/C++->General.

4. The first line in the list view, should say "Additional Include Directories", and any additional directories that contain include files there. You can specify the full path (C:/myproject/blah/blah/includes), or a relative path (../../../blah/includes).

[jom20]

Thanks HeartBreakKid, I tried it and it worked.

[Andreas Masur]

Originally posted by jom20
The block code is:

typedef struct
{
uint16 uiCom;
boolean block;
}TxAdmin


I dont understand what this means.
This defines a new datatype named 'TxAdmin' which is a structure. This is the old ANSI C way of defining structure types. In C++ however, this is not necessary any longer since 'struct' will already define a new type. Nevertheless, the above will also work with any C++ compiler...

[jom20]

Thanks Andreas.

I was a bit lost on that one. Do you know of any sites apart from msdn.microsoft.com that explains the language structure.

Thanks
Trisha

[Andreas Masur]

Originally posted by jom20
Do you know of any sites apart from msdn.microsoft.com that explains the language structure.

Well...to be honest...not really. I could name books rather than websites. However, using any search engine like e.g. Google should return many sites... :cool: