Com Ports - C / C++ / MFC Discussion Boards

ExitWindowsEx

john563221-Apr-08 19:37

john5632

21-Apr-08 19:37

Hi,

The below code is not working:
ExitWindowsEx(EWX_REBOOT|EWX_FORCE,0);

In which condition it may fail?

Re: ExitWindowsEx

Hamid_RT21-Apr-08 19:47

Hamid_RT

21-Apr-08 19:47

Whats the return value ? and see A tool to perform automatic shutdown, log off or restart action[^].

Re: ExitWindowsEx

john563221-Apr-08 20:13

john5632

21-Apr-08 20:13

Return value is 0. And I have checked this.

Re: ExitWindowsEx

Rajkumar R21-Apr-08 20:19

Rajkumar R

21-Apr-08 20:19

not that, what's the return value of GetLastError().

possibly the privilege issue, The application must first enable the SE_SHUTDOWN_NAME privilege[^]

Re: ExitWindowsEx

john563221-Apr-08 20:20

john5632

21-Apr-08 20:20

Using getLastError, I got the error 1314 (The required previlige is not held by the client). What it means?

Re: ExitWindowsEx

Rajkumar R21-Apr-08 20:24

Rajkumar R

21-Apr-08 20:24

pther wrote:
What it means?

see my previous reply

Re: ExitWindowsEx

Hamid_RT21-Apr-08 20:34

Hamid_RT

21-Apr-08 20:34

Did you see my link?

Com Ports

usyra4221-Apr-08 19:34

usyra42

21-Apr-08 19:34

Hello Friends,

Can anyone say how to find the number of ports and the name of ports such as COM1, COM2 etc in our PC using a VC++ program. I searched it everywhere, but i couldnt find a proper source code.
Can u please help in this..

usharani

Re: Com Ports

Rajkumar R21-Apr-08 19:43

Rajkumar R

21-Apr-08 19:43

Serial ports. Enumeration [^] may be useful

usyra42 wrote:
searched it everywhere

Re: Com Ports

usyra4221-Apr-08 20:35

usyra42

21-Apr-08 20:35

It is Very confusing because we dont have complete source code there .
Can u help me in this

usharani

Re: Com Ports

Rajkumar R21-Apr-08 20:45

Rajkumar R

21-Apr-08 20:45

don't you have the implementation of BeginEnumeratePorts, EnumeratePortsNext, EndEnumeratePorts posted in the page itself.

Re: Com Ports

usyra4221-Apr-08 21:58

usyra42

21-Apr-08 21:58

Hi Raj thanks very much it was helpful a lot..................

usharani

speed up serial communication

vijay.victory21-Apr-08 19:21

vijay.victory

21-Apr-08 19:21

Hi experts,

I m a VC++ developer and i used Windows API CreateFile() for serial communication. but it decrease the speed of sending n receiving bytes from port.

can u please answer me how to speed up communication?

I also set the TimeOuts to '0' so that it doesnt take any timeout waitng..

Please reply..

Its really matter to me..

Re: speed up serial communication

Cedric Moonen21-Apr-08 20:21

Cedric Moonen

21-Apr-08 20:21

Member 3220373 wrote:
but it decrease the speed of sending n receiving bytes from port.

What do you mean ? Decrease compated to what ? Confused | :confused:

Cédric Moonen
Software developer

Charting control [v1.4 - Updated]

Re: speed up serial communication

vijay.victory22-Apr-08 0:07

vijay.victory

22-Apr-08 0:07

the time taken by my program in VC++ is very greater than same implemented
program in TurboC++

My observation;;

if i used a file to write on device connected on my COM4 have size 172kb

then TurboC++ pgm takes only 54sec but VC++ pgm takes 211 sec

almost 3.5 times.

so i want some special function or tric to increase the speed of this transmisssion..

reply...plzzzzzzz

Re: speed up serial communication

CPallini21-Apr-08 21:45

CPallini

21-Apr-08 21:45

Member 3220373 wrote:
can u please answer me how to speed up communication?

Use USB. (just kidding).

Please elaborate.
Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

Re: speed up serial communication

Randor 21-Apr-08 22:53

Randor

21-Apr-08 22:53

Overlapped I/O[^] will give you better results than synchronous blocking calls to WriteFile and ReadFile. The examples at Microsoft show you how to do it.

http://msdn2.microsoft.com/en-us/library/ms810467.aspx[^]

This article may also be useful:

http://www.codeproject.com/KB/system/serial_com.aspx[^]

Best Wishes.
-David Delaune

Re: speed up serial communication

vijay.victory22-Apr-08 0:16

vijay.victory

22-Apr-08 0:16

Thnks for reply...

I already used DCB structure in my program..

but have same effect...

the probm is If i load a file of 172kb using TurboC++ prgm

then it takes appx 55 sec...
but
when I load file using VC++ prgm that uses CreateFile() API
it takes appx 211 sec... i.e. appox 3.5 times.of TC

so plz... reply....any option to decrease load delay..

n speed up my transmission...

PLz ..... ur reply always matter to me..

Can we draw a child window outside the client area of the parent?

misha_grewal21-Apr-08 19:12

misha_grewal

21-Apr-08 19:12

I am trying to implement "intellisearch" combo box like we have in IE.

I create a separate list box and draw it below combo box when user starts typing in something.
The Combo box has to be a parent of this list box. When I draw the list box using the Create method, it offcourse will try to draw the list box inside the client area of the combo box, and fails to do so.

Can we draw a child window outside the client area of the parent?

<br />
<br />
bool CAutoCompComboBox::CreateListBox()<br />
{<br />
   CRect clientRect(-1, -1, -1, -1);<br />
<br />
   GetClientRect(&clientRect);  <br />
  // adjust the height to be like a list box<br />
<br />
BOOL bRet =  _listFilter.Create(WS_CHILD | WS_VISIBLE | <br />
                                   WS_VSCROLL | LBS_STANDARD,<br />
                                   clientRect, this, 1);<br />
<br />
// the window is created but not seen here. <br />
// however this code works, obviously because I give the parent as <br />
// dialog box which is holding the AutoCompComboBox control. <br />
<br />
_listFilter.Create(WS_CHILD | WS_VISIBLE | <br />
                                   WS_VSCROLL | LBS_STANDARD,<br />
                                   clientRect, GetParent(), 1);<br />
<br />
<br />

Thanks in advance..

Misha

Evil triumphs when good people sit quiet...

Re: Can we draw a child window outside the client area of the parent?

Rajkumar R21-Apr-08 19:20

Rajkumar R

21-Apr-08 19:20

I would suggest using the listbox comes with combobox instead of creating a new listbox. CComboBox::ShowDropDown()[^]

Re: Can we draw a child window outside the client area of the parent?

misha_grewal21-Apr-08 20:28

misha_grewal

21-Apr-08 20:28

Thanks,
Thats the problem. I don't want to subclass the list box which comes with CCombobox. I have to keep it separate.

all ideas would be greatly appreciated.

Evil triumphs when good people sit quiet...

Re: Can we draw a child window outside the client area of the parent?

Rajkumar R21-Apr-08 20:54

Rajkumar R

21-Apr-08 20:54

what about WS_POPUP style instead of WS_CHILD and position the popup window relative to combobox and send the messages to and fro between combo box and popup listbox. I think popup window is the best match as "intellisearch" kind of control pops up when some thing is typed and closes when out of focus from combobox.

Re: Can we draw a child window outside the client area of the parent?

misha_grewal22-Apr-08 0:07

misha_grewal

22-Apr-08 0:07

Thanks, that seems to work. the code looks like this:

 ClientToScreen(&clientRect); <br />
<br />
   BOOL bRet =  _listFilter.CreateEx(0, <br />
                                    _T("LISTBOX"), <br />
                                    _T(""), <br />
                                    WS_POPUP | WS_VISIBLE | WS_BORDER | WS_VSCROLL <br />
                                    | LBS_NOTIFY <br />
                                    ,<br />
                                    clientRect.left, clientRect.top, <br />
                                    clientRect.Width(), clientRect.Height(), <br />
                                    this->GetSafeHwnd(), <br />
                                    NULL, <br />
                                    NULL);<br />

Evil triumphs when good people sit quiet...

VC++ Doubt

sachinjoseph21-Apr-08 19:00

sachinjoseph

21-Apr-08 19:00

How can I design a compiler (I dont need statement parsing or evaluating expressions, but how to generate Windows PE Code)
How can an EXE file be built from my compiler?

Re: VC++ Doubt

Hamid_RT21-Apr-08 19:44

Hamid_RT

21-Apr-08 19:44

Design a compiler you need to lot of info and its very difficult but for make a exe file I think(not sure) I saw a article on the www.codeguru.com that it explained about exe files(PE,...) and very other useful info.

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