C / C++ / MFC

20-Aug-07 5:16

I'm in need to detect whether a network connection is established using a WLAN or a LAN. I don't know in what way the detection is different ..

Thanks for any help ..
HStrix

David Crow20-Aug-07 5:21

20-Aug-07 5:21

HStrix wrote:
I'm in need to detect whether a network connection is established using a WLAN or a LAN.

Have you considered something like IsNetworkAlive()?

"A good athlete is the result of a good and worthy opponent." - David Crow

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

HStrix20-Aug-07 5:32

20-Aug-07 5:32

Thanks DavidCrow,
I did not yet consider IsNetworkAlive().
But I checked it now in the internet
and found that it can only decide between LAN and WAN Frown | :(

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/syncmgr/syncmgr/isnetworkalive.asp

David Crow20-Aug-07 5:37

20-Aug-07 5:37

HStrix wrote:
...and found that it can only decide between LAN and WAN

And yet those were your exact requirements. Roll eyes | :rolleyes:

"A good athlete is the result of a good and worthy opponent." - David Crow

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

HStrix20-Aug-07 5:45

20-Aug-07 5:45

Sorry, perhaps there is some misunderstanding ..
I want to decide between WLAN und LAN
and not between WAN and LAN ..

David Crow20-Aug-07 5:56

20-Aug-07 5:56

HStrix wrote:
Sorry, perhaps there is some misunderstanding ..

Yes, I failed to realize W was for Wireless not Wide. Blush | :O

You can use GetAdaptersInfo() for this. With the adapter name from that, call CreateFile() to get a handle, and call DeviceIOControl(..., IOCTL_NDISUIO_QUERY_OID_VALUE, ...). I've not fully tried this, however.

"A good athlete is the result of a good and worthy opponent." - David Crow

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

HStrix20-Aug-07 6:07

20-Aug-07 6:07

Thank you,
this looks good.
I'll give it a try.
Maybe it takes some time ..

L macro

George_George20-Aug-07 5:11

20-Aug-07 5:11

Hello everyone,

I am using Visual Studio 2003 and Windows Console project, I find when using L macro to convert character to wide character, the compiler will report an error that L macro is not defined.

I find it is not defined in either <windows.h> or <tchar.h> -- when adding the two header files, the compile error is the same.

Could anyone explain how to use L macro in Visual Studio 2003 and Windows Console project? Which header file is needed?

thanks in advance,
George

David Crow20-Aug-07 5:25

20-Aug-07 5:25

George_George wrote:
...I find when using L macro to convert...

Technically speaking, I do not believe L is a macro.

George_George wrote:
the compiler will report an error that L macro is not defined.

What does the offending statement look like?

"A good athlete is the result of a good and worthy opponent." - David Crow

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

George_George20-Aug-07 17:07

20-Aug-07 17:07

Thanks David,

The statement is simple, something like, L"hello". Why do you think it is not a macro? Who to use L in Visual Studio 2003 Windows Console project?

regards,
George

David Crow20-Aug-07 17:14

20-Aug-07 17:14

If it were a macro (i.e. preprocessor directive), it would resolve to something.

"A good athlete is the result of a good and worthy opponent." - David Crow

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

George_George20-Aug-07 17:45

20-Aug-07 17:45

Hi David,

If it is not a macro, what is it?

regards,
George

David Crow20-Aug-07 17:51

20-Aug-07 17:51

George_George wrote:
If it is not a macro, what is it?

It's simply a prefix to denote wide-string literals.

"A good athlete is the result of a good and worthy opponent." - David Crow

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

George_George20-Aug-07 19:19

20-Aug-07 19:19

Thanks David,

I can understand your point. I mean there should be a technical terminology to call it -- besides the term "prefix". So, if it is not macro, what is it? There is not a technical terminology called "prefix". Smile | :)

regards,
George

toxcct20-Aug-07 22:11

toxcct

20-Aug-07 22:11

George_George wrote:
If it is not a macro, what is it?

it's an extended keyword of the language

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George_George20-Aug-07 22:27

20-Aug-07 22:27

Thanks toxcct,

I want to confirm that keyword L could only be used in C++ and not in C. Right?

regards,
George

toxcct20-Aug-07 22:37

toxcct

20-Aug-07 22:37

George_George wrote:
want to confirm that keyword L could only be used in C++ and not in C

then why didn't you asked clearly ?
and why do you bother that much ? why is it that important ?
can't you just search the WEB for that easy info ?

BTW, what is it that you vote everybody to '4' ???

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George_George21-Aug-07 1:05

21-Aug-07 1:05

Thanks toxcct,

I can not find answer from MSDN so I come here. We could only use L in C++? Can not use in C?

regards,
George

Iain Clarke, Warrior Programmer

Iain Clarke, Warrior Programmer20-Aug-07 5:39

20-Aug-07 5:39

As has been said, L is not a macro...

char narrow [] = "abc";
TCHAR either [] = _T("abc"); // uses a macro
wchar_t wide [0] = L"abc";

short a = 1L; // will give a warning at least

The last example shows that L is also useful for non-chars, etc.

Iain.

George_George20-Aug-07 17:13

20-Aug-07 17:13

Thanks Iain,

You code can not compile in my VS 2003 environment,

This statement

wchar_t* wide [] = L"abc";

error C2075: 'wide' : array initialization needs curly braces

When I change to L("hello"), there is an error from compiler that L is undefined.

regards,
George

Maxwell Chen20-Aug-07 19:39

Maxwell Chen

20-Aug-07 19:39

George_George wrote:
can not compile in my VS 2003 environment,
This statement
wchar_t* wide [] = L"abc";
error C2075: 'wide' : array initialization needs curly braces
When I change to L("hello"), there is an error from compiler that L is undefined.

The below works fine with Visual Studio 2005.

char narrow [] = "abc";
wchar_t wide [] = L"abc";
short a = 1L; // will give a warning at least

Maxwell Chen

George_George20-Aug-07 20:17

20-Aug-07 20:17

Thanks Maxwell,

I have verified that it is ok.

regards,
George

LPCSTR and LPCWSTR

George_George20-Aug-07 4:56

20-Aug-07 4:56

Hello everyone,

I think when UNICODE or _UNICODE is defined, when using _T, it could convert characters to wide character.

And I also think LPCSTR should be defined to pointer to wide character when UNICODE or _UNICODE is defined, and LPCSTR should be defined to pointer to multibyte character when UNICODE and _UNICODE are not defined.

But it seems I am wrong for all points. Could anyone explain to me why I get such warnings in Visual Studio 2003?

<br />
#include "windows.h"<br />
#include "TCHAR.h"<br />
<br />
#define UNICODE<br />
#define _UNICODE<br />
<br />
int main (int argc, char** argv)<br />
{<br />
        WCHAR* p = _T("hello");<br />
        LPCSTR p1 = p;<br />
        LPCWSTR p2 = p;<br />
}<br />

warning messages,

warning C4133: 'initializing' : incompatible types - from 'char [6]' to 'WCHAR *'
warning C4133: 'initializing' : incompatible types - from 'WCHAR *' to 'LPCSTR'

thanks in advance,
George

Re: LPCSTR and LPCWSTR

David Crow20-Aug-07 5:31