Re: Socket creatinon in debug mode - C / C++ / MFC Discussion Boards

Mark Salsbery26-Jun-07 6:48

26-Jun-07 6:48

If the exception is in your code, then what's the code causing the exception?

If the first-chance exception occurs in another module, but the app continues to run normally,
then the exception was handled by the other module.

Try continuing to step through the code after the first-chance exception - if the exception isn't
handled you'll find out very soon Smile | :)

Mark

"Go that way, really fast. If something gets in your way, turn."

Re: Socket creatinon in debug mode

Zoltan Balazs26-Jun-07 7:15

Zoltan Balazs

26-Jun-07 7:15

Mark Salsbery wrote:
If the exception is in your code, then what's the code causing the exception?

I don't know. It runs without any exceptions in debug and release mode. Only when stepping through in the IDE throws an exception.
The code is something like:

<br />
	smtpSocket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);<br />
	if (smtpSocket == INVALID_SOCKET) <br />
	{<br />
		throw "Can't create socket ...";<br />
		WSACleanup();<br />
		return;<br />
	}<br />

It throws an exception at the socket call and if I continue it throws another at the WSACleanup call.
The strange thing is that it only occurs, as I sad when stepping through the code.

Network integrated solutions
A practical use of the MVC pattern

Re: Socket creatinon in debug mode

Mark Salsbery26-Jun-07 7:23

Mark Salsbery

26-Jun-07 7:23

Have you called WSAStartup() somewhere?

Mark

"Go that way, really fast. If something gets in your way, turn."

Re: Socket creatinon in debug mode

Zoltan Balazs26-Jun-07 8:18

Zoltan Balazs

26-Jun-07 8:18

Mark Salsbery wrote:
Have you called WSAStartup() somewhere?

Yep. Just a couple of lines before Smile | :)

<br />
	int errorCode = WSAStartup(MAKEWORD (2,2), &wsdata);<br />
	if (errorCode !=0)<br />
	{<br />
		ThrowWsaError(errorCode);<br />
		return;<br />
	}<br />
<br />
	if (LOBYTE(wsdata.wVersion) != 2 || HIBYTE(wsdata.wVersion) != 2) <br />
	{<br />
		throw "Winsock DLL version error ...";<br />
		WSACleanup();<br />
		return;<br />
	}<br />
	<br />
	smtpSocket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); <br />

The truth is that I also tried another example (an excerpt from a book) and it happening there also. I tried with VC6, VS2005.
Anyway it runs fine just the question "why" bothers me...

Network integrated solutions
A practical use of the MVC pattern

Re: Socket creatinon in debug mode

Mark Salsbery26-Jun-07 8:50

Mark Salsbery

26-Jun-07 8:50

Zoltan Balazs wrote:
It throws an exception at the socket call and if I continue it throws another at the WSACleanup call.

If the socket() call is failing, and you get to the WSACleanup() call, that doesn't sound like
it's running fine.

Strange Smile | :)

"Go that way, really fast. If something gets in your way, turn."

Re: Socket creatinon in debug mode

Zoltan Balazs26-Jun-07 8:58

Zoltan Balazs

26-Jun-07 8:58

I know.
Try it Wink | ;)

Network integrated solutions
A practical use of the MVC pattern

Re: Socket creatinon in debug mode

Mark Salsbery26-Jun-07 9:03

Mark Salsbery

26-Jun-07 9:03

I did!

On a Win32/Multithread DLL CRT/Unicode build, running VS2003 .NET on XP Pro SP2.

I wish I COULD reproduce it! That would make a possible solution SO much easier Smile | :)

Just to make sure I'm following...On the same build, it runs fine outside the debugger
environment (including getting an actual valid, working socket), but when run in the debugger,
the socket() call fails, yet none of the exceptions go beyond first-chance (meaning they were
handled). Is that correct?

Mark

"Go that way, really fast. If something gets in your way, turn."

Re: Socket creatinon in debug mode

Zoltan Balazs26-Jun-07 21:01

Zoltan Balazs

26-Jun-07 21:01

Mark Salsbery wrote:
Just to make sure I'm following...

Yes, that's correct.

I tried and reproduced also using VS2003 on XP Pro SP2.
The compiler command line is

/Od /D "WIN32" /D "_DEBUG" /D "_CONSOLE" /D "_MBCS" /Gm /EHsc /RTC1 /MT /Fo"Debug/" /Fd"Debug/vc70.pdb" /W3 /nologo /c /Wp64 /ZI /TP

and I'm linking against ws2_32.lib.
All has the default settings, just created an empty console project and added ws2_32.lib to the linker.

And thanks for taking the time to check this out.

Network integrated solutions
A practical use of the MVC pattern

Re: Socket creatinon in debug mode

Mark Salsbery27-Jun-07 5:17

Mark Salsbery

27-Jun-07 5:17

I tried your code again on VS 2005 Express (I usually use 2003 .NET) and was still unable to
reproduce it.

I wonder if something is up with your TCP configuration. Here's the output messages I get at
the calls in question...

socket(...)
'TestWin32Console.exe': Loaded 'C:\WINDOWS\system32\wshtcpip.dll', No symbols loaded.

WSACleanup()
'TestWin32Console.exe': Unloaded 'C:\WINDOWS\system32\wshtcpip.dll'
'TestWin32Console.exe': Unloaded 'C:\WINDOWS\system32\hnetcfg.dll'

Something may be failing in your wshtcpip.dll, causing the exception.

Otherwise, I have no clue on this one. I've never had the same problem using Winsock2 and I
haven't heard of others with the same problem either Confused | :confused:

If I think of something I'll definitely let you know!
Mark

"Go that way, really fast. If something gets in your way, turn."

Re: Socket creatinon in debug mode

Zoltan Balazs27-Jun-07 5:54

Zoltan Balazs

27-Jun-07 5:54

The strange thing is if I press "Ignore" the socket creation will succeed and I can debug my app.
I will try this on another computer.

Network integrated solutions
A practical use of the MVC pattern

Re: Socket creatinon in debug mode

Mark Salsbery27-Jun-07 6:41

Mark Salsbery

27-Jun-07 6:41

I guess maybe it's ok then, if the socket is created successfully.

First chance exceptions in the debugger are only notifications - you can actually turn them off
so the debugger won't break at the first chance exception but instead will just write a message
to the output window.

Only if the exception goes unhandled - then it's a problem. If you can continue on without
problem after a first-chance exception then that means the exception was handled.

I've just never seen a first-chance exception using sockets Smile | :)

Mark

"Go that way, really fast. If something gets in your way, turn."

Re: Socket creatinon in debug mode

Zoltan Balazs27-Jun-07 7:05

Zoltan Balazs

27-Jun-07 7:05

I tried to turn off the first chance exceptions as shown here http://www.helixoft.com/blog/archives/24[^].
No success though... I still have to try to reproduce this on another computer. I'll get back with results. Smile | :)

Thanks again for the time.

Network integrated solutions
A practical use of the MVC pattern

How to save System Log In & Log Off Times

Nagaraju_Focus25-Jun-07 22:00

Nagaraju_Focus

25-Jun-07 22:00

Hi All,
My Task in vc++ is to save System LogIn and LogOff Times ,Date in A TextFile.
I have No Idea of How to Do.
I search a lot in Net But Unable to get my Requirement

Plz Suggest me to get rid of this.

Thanks In Advance

Nagaraju

Re: How to save System Log In & Log Off Times

Hamed Musavi25-Jun-07 22:25

Hamed Musavi

25-Jun-07 22:25

In Windows, I think there's already a logger. check Event Viewer in 'Administrative Tools' in Control panel.

If you still stick with using a text file with your app, you may consider developing an NT Service that after startup and before shutdown of the service gets the current time and date using a time class like:CTime and stores it in a text file.

For writing a simple service Nishant.S. already wrote a perfect article here in CP.

// "Life is very short and is very fragile also." Yanni
while (I'm_alive)
{
cout<<"I love programming.";
}

Class derived from CDialog

prithaa25-Jun-07 21:44

prithaa

25-Jun-07 21:44

Hello,

I want to derive a class from CDialog without resource-ID. How should I use InitModalIndirect() for the dialog initialization?
How should I use DLGTEMPLATE and DLGITEMTEMPLATE structure for the derived class?

Prithaa

Re: Class derived from CDialog

Hamid_RT25-Jun-07 22:30

Hamid_RT

25-Jun-07 22:30

Do you need to see Dynamic Dialog Class[^]

WhiteSky

Re: Class derived from CDialog

Mark Salsbery26-Jun-07 6:56

Mark Salsbery

26-Jun-07 6:56

prithaa wrote:
How should I use DLGTEMPLATE and DLGITEMTEMPLATE structure for the derived class?

That depends on where the dialog template is going to come from. Will you be loading it as a
resource from a module? Will you be creating a template in memory?

The DLGTEMPLATE[^] documentation explains how these structs need to be layed out in memory.

Mark

"Go that way, really fast. If something gets in your way, turn."

Totally confused with memory alocation for '_get_pgmptr' function [modified]

Hamed Musavi25-Jun-07 21:30

Hamed Musavi

25-Jun-07 21:30

Problem solved. Thanks. Rose | [Rose]

I need to use this function in c++ console app, and the documentation says:

errno_t <code>_get_pgmptr</code>( char **pValue );

pValue
A pointer to a string to be filled with ...

So I did this:

	char *path = new char[MAX_PATH+1];
	memset(path, NULL, MAX_PATH + 1);

	<code>_get_pgmptr</code>(&path);
...
        delete[] path;

But the call to the function, changes the address of the pointer(path) and calling the delete will fail.
I thought first that perhaps, I don't need to allocate any memory and the function (oddly) allocates it automatically and sends me the address but this is not the case either. Can anyone tell me what's wrong with this?

-- modified at 8:18 Tuesday 26th June, 2007

Re: Totally confused with memory alocation for '_get_pgmptr' function

Rajkumar R25-Jun-07 21:58

Rajkumar R

25-Jun-07 21:58

Hi,
It gets the current value of the _pgmptr, a global variable which contains the file path. You need not allocate the buffer.
What happen if you pass without allocating?

Re: Totally confused with memory alocation for '_get_pgmptr' function

Hamed Musavi25-Jun-07 22:16

Hamed Musavi

25-Jun-07 22:16

I found the problem was another mistake! You're right and the function gets a pointer to that variable.

I forgot to remove my question here, I guess I posted too soon, before investigating the code completely. Sorry!

Anyway, Thanks a lot for your attention and reply. Smile | :)

// "Life is very short and is very fragile also." Yanni
while (I'm_alive)
{
cout<<"I love programming.";
}

Re: Totally confused with memory alocation for '_get_pgmptr' function

KaЯl25-Jun-07 22:48

KaЯl

25-Jun-07 22:48

No need to strike your question, it could be useful for others Smile | :)

The most wasted of all days is that on which one has not laughed

Fold with us! ¤ flickr

Re: Totally confused with memory alocation for '_get_pgmptr' function

Hamed Musavi26-Jun-07 2:19

Hamed Musavi

26-Jun-07 2:19

Done.

// "Life is very short and is very fragile also." Yanni
while (I'm_alive)
{
cout<<"I love programming.";
}

Re: Totally confused with memory alocation for '_get_pgmptr' function

KaЯl26-Jun-07 2:39

KaЯl

26-Jun-07 2:39

Thanks from the community Smile | :)

When they kick at your front door
How you gonna come?
With your hands on your head
Or on the trigger of your gun?

Fold with us! ¤ flickr

What is the error in this code fragment

xbiju25-Jun-07 21:16

xbiju

25-Jun-07 21:16

Why does te following C++ code flag error?

# include

const int i=10;
void main()
{
const int i = 20;
cout << i << endl << ::i;
cout << &i;
}

The error flagged is "Illegal structure operation in main"
Compiler use : Borland C++ 4.5
How can I access the address of the local and global constant 'i's?

Please help me.

Thanks,

Biju

Re: What is the error in this code fragment

Hamed Musavi25-Jun-07 21:33

Hamed Musavi

25-Jun-07 21:33

Nothing is in front of #include

// "Life is very short and is very fragile also." Yanni
while (I'm_alive)
{
cout<<"I love programming.";
}

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.