If I want to ask C/C++ question under Linux environment. - C / C++ / MFC Discussion Boards

Re: Dialog box pops up and vanishes immediately

Frank K23-Jul-03 0:56

23-Jul-03 0:56

Hi,

from which type is your application? (e.g. dialog-based)

Why do you set the m_pMainWnd variable to current dialog? Because if your application dialog based and the m_pMainWnd = current dialog and the dialog close, then the application get a "signal" that the mainwindow is closed and the application terminates itself.

Regards Frank

Re: Dialog box pops up and vanishes immediately

David Crow23-Jul-03 3:44

David Crow

23-Jul-03 3:44

Right. While not exactly the same, I bet it is closely related to MSDN article Q138681.

Re: Dialog box pops up and vanishes immediately

wb23-Jul-03 1:48

23-Jul-03 1:48

There is an article about "Dialog Tips & Trics" on CP.
read it! Wink | ;)

I guess its because m_pMainWnd

Enumerates LPT

Eugene Pustovoyt22-Jul-03 22:16

Eugene Pustovoyt

22-Jul-03 22:16

How can enumerate LPT ports on machine?
If possible, with sample code please.

Best regards,
Eugene Pustovoyt

Re: Enumerates LPT

Alexander ^M.,23-Jul-03 1:54

Alexander ^M.,

23-Jul-03 1:54

i don't know anything about coding with LPT ports...
but try this:

char buffer[32];<br />
unsigned int i;<br />
HANDLE hPort;<br />
<br />
for( i = 1; i < 10; i++ )<br />
{<br />
  sprintf( buffer, "LPT%i", i );<br />
  hPort = CreateFile( buffer, GENERIC_READ, 0, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL )<br />
  <br />
  if( hPort == INVALID_HANDLE_VALUE )<br />
    break; // -> i - 1 = last lpt port<br />
<br />
  CloseHandle( hPort );<br />
}<br />

Don't try it, just do it! Wink | ;-)

Re: Enumerates LPT

Iain Clarke, Warrior Programmer23-Jul-03 1:59

Iain Clarke, Warrior Programmer

23-Jul-03 1:59

Your question intrigued me, as not long ago there were a series of articles / questions on
how impossible it was to enumerate serial ports...

I've done a little digging, and there are two functions that should interest you:
EnumPorts and EnumPrinters.

Here is some sample code for each:

DWORD dwNeed = 0;
DWORD dwPorts = 0;

BOOL b = EnumPorts (NULL, 2, NULL, dwNeed, &dwNeed, &dwPorts);
if (!b && GetLastError () == ERROR_INSUFFICIENT_BUFFER)
{
    BYTE *buf = new BYTE [dwNeed];
    memset (buf, 0, dwNeed);

    PORT_INFO_2 *p = (PORT_INFO_2 *)buf;

    b = EnumPorts (NULL, 2, buf, dwNeed, &dwNeed, &dwPorts);

    delete [] buf;
}

dwNeed = dwPorts = 0;
b = EnumPrinters (PRINTER_ENUM_LOCAL, NULL, 1, NULL, dwNeed, &dwNeed, &dwPorts);
if (!b && GetLastError () == ERROR_INSUFFICIENT_BUFFER)
{
    BYTE *buf = new BYTE [dwNeed];
    memset (buf, 0, dwNeed);
    PRINTER_INFO_1 *p = (PRINTER_INFO_1 *)buf;

    b = EnumPrinters (PRINTER_ENUM_LOCAL, NULL, 1, buf, dwNeed, &dwNeed, &dwPorts);

    delete [] buf;
}

You may also want to look at EnumMonitors, and the results different report levels give.

Iain.

Re: Enumerates LPT

Eugene Pustovoyt23-Jul-03 3:29

Eugene Pustovoyt

23-Jul-03 3:29

Thank you. That's all I need

Best regards,
Eugene Pustovoyt

If I want to ask C/C++ question under Linux environment.

George222-Jul-03 21:54

George2

22-Jul-03 21:54

Hello, everyone!

If I want to ask question about C/C++ under Linux environment. Can you introduce some forums?

regards,
George

Re: If I want to ask C/C++ question under Linux environment.

Alexander ^M.,23-Jul-03 1:56

Alexander ^M.,

23-Jul-03 1:56

this is a windows site

Don't try it, just do it! Wink | ;-)

Re: If I want to ask C/C++ question under Linux environment.

George223-Jul-03 3:01

George2

23-Jul-03 3:01

Hi, Alexander buddy!

Linux is our future. Smile | :)

Can you answer my question in a direct way? Smile | :)

Thanks in advance,
George

Re: If I want to ask C/C++ question under Linux environment.

roel_23-Jul-03 2:01

roel_

23-Jul-03 2:01

What do you want to know? What is Linux-specific about it? If it's about a library, ask on that libraries mailing list; if it's not Linux specific, ask here.

Re: If I want to ask C/C++ question under Linux environment.

George223-Jul-03 3:00

George2

23-Jul-03 3:00

Thanks, roel_ buddy!

I want to ask IPC, PThread, memory management and device driver questions under Linux environment.

Do you know some forums?

regards,
George

Re: If I want to ask C/C++ question under Linux environment.

David Crow23-Jul-03 3:41

David Crow

23-Jul-03 3:41

Have you checked out any of the linux.dev.* newsgroups?

Re: If I want to ask C/C++ question under Linux environment.

George223-Jul-03 3:46

George2

23-Jul-03 3:46

A very nice idea!

But are there some web based?

George

Re: If I want to ask C/C++ question under Linux environment.

David Crow23-Jul-03 3:51

David Crow

23-Jul-03 3:51

You can access them from Google.

Re: If I want to ask C/C++ question under Linux environment.

George224-Jul-03 2:44

George2

24-Jul-03 2:44

Thanks, DavidCrow buddy!

George

Re: If I want to ask C/C++ question under Linux environment.

roel_23-Jul-03 5:02

roel_

23-Jul-03 5:02

You could start with http://leapster.org/linoleum/ (I admit, it's the second link when you type 'linux programming' in Google). Find some mailing lists to subscribe to, most development and support is on mailing lists and not on web-based boards in the Linux world (suggestion: get yourself a threading mail reader, like Mozilla Mail or even better, Mutt, it will greatly enhance your mailing list reading)

Re: If I want to ask C/C++ question under Linux environment.

George224-Jul-03 2:43

George2

24-Jul-03 2:43

Thanks, roel_ buddy!

It is a very nice site!! Smile | :)

George

what is stdin and its friends?

Newborn Naughtysaint22-Jul-03 21:43

Newborn Naughtysaint

22-Jul-03 21:43

everybody knows what is the meaning of stdin, stdout, stderr, stdaux, and stdprm?
i just know those are standard input device, standard out device, and so on ...
but i don't have any idea(i don't understand) about standard input device, and its friends.
can somebody explain to me?

thousands thanx Smile | :)

>>when someone know more and more, they will feel they have weakness<<

Re: what is stdin and its friends?

jhwurmbach22-Jul-03 22:16

jhwurmbach

22-Jul-03 22:16

They are io-streams that are opened by the runtime lib for you. Stdin is by connected to the console by default (but may be connected to some file with '<' on the command line.
Stdout is connected to to a console window on the screen by default, but can be redirected to a file with '>' on the command line.
Stderr is by default connected like stdin, but can not be redirected.

I hope this could help you a bit.

My opinions may have changed, but not the fact that I am right.

Re: what is stdin and its friends?

Bob Stanneveld23-Jul-03 2:02

Bob Stanneveld

23-Jul-03 2:02

Those are just streams! just like any files streams, memory streams,...
You should find all the information you need in the MSDN library Smile | :)

A student knows little about a lot.
A professor knows a lot about little.
I know everything about nothing.

Share combobox on different pages

harmendejong22-Jul-03 21:40

harmendejong

22-Jul-03 21:40

I want to achieve the following:

Suggest you have a property sheet with three property pages which all have a combobox named IDC_COMBOBOX. The comboboxes named IDC_COMBOBOX, all have te same items stored in it. The list of items is large, so it takes a wile to put (initialize) all the items into the combobox. Therefore I want all the three comboboxes to share the same list of items, so that I only have to initialize one time to get all the three comboboxes filled with the same items.
How can I achieve this?
Is there a way to access the storage of the combobox from another dialog?

Thnxx

Re: Share combobox on different pages

zeki yugnak22-Jul-03 23:14

zeki yugnak

22-Jul-03 23:14

harmendejong wrote:
Is there a way to access the storage of the combobox from another dialog?

yes.

first of all, you should determine DDX object for your control(m_combo) in CYourDialog1 and then you can access to control from other dialog that follow this.

//in CYourDialog<br />
CYourDialog1 dlg;<br />
dlg.m_combo......

Re: Share combobox on different pages

harmendejong22-Jul-03 23:42

harmendejong

22-Jul-03 23:42

On that way I can access the data of the other combobox, but actually I want al the (three) comboboxes to act like they are the same. So if I've added a large list of items to combobox1, then combobox2 and combobox3 must automatically have that items too without having to load the large list of items into their storage area in the memory. I think this could be done if they all use the same area of memory for the storage of their items.
How can this be done???

Re: Share combobox on different pages

Ryan Binns22-Jul-03 23:31

Ryan Binns

22-Jul-03 23:31

harmendejong wrote:
Is there a way to access the storage of the combobox from another dialog?

No, you can't have two combo boxes share the same data. However, to speed up the loading process, use SetRedraw() on the combo boxes (if you're using MFC, send the WM_SETREDRAW message to the combo box if you're not) to prevent the combo box updating itself after each addition. Remember to call it again when you've finished loading data to enable updating again, and then call Invalidate() on the combo box.

Hope this helps,

Ryan

"Punctuality is only a virtue for those who aren't smart enough to think of good excuses for being late" John Nichol "Point Of Impact"

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