C / C++ / MFC Discussion Boards

Zac Howland6-Sep-06 9:08

6-Sep-06 9:08

If the memory for those strings is on the stack, when the scope that is adding them to the map is complete (e.g. the function finishes) all that memory is now invalid. You may still have "valid" data for a while, but all that stack memory is no unallocated/unprotected and will be overwritten eventually. That will cause problems later, if it isn't already.

If you decide to become a software engineer, you are signing up to have a 1/2" piece of silicon tell you exactly how stupid you really are for 8 hours a day, 5 days a week

Zac

Re: Errors Using CMap Collections

nadiric6-Sep-06 10:41

nadiric

6-Sep-06 10:41

So, are you saying that the map does not make copies of the string data, but simply points to the strings I'm sending in?

If so, that's useless to me, any way around this?

Re: Errors Using CMap Collections

Zac Howland7-Sep-06 4:48

Zac Howland

7-Sep-06 4:48

LPCTSTR is not a string, it is either a const char* or a const wchar_t* depending on whether UNICODE is defined or not. So, yes, the CMap class copies the pointer, but not the string (because it doesn't know you are passing it a string).

To get around that, declare your map type as CMap<CString, CString&, int, int>

If you decide to become a software engineer, you are signing up to have a 1/2" piece of silicon tell you exactly how stupid you really are for 8 hours a day, 5 days a week

Zac

Re: Errors Using CMap Collections

nadiric7-Sep-06 5:23

nadiric

7-Sep-06 5:23

Bingo!

Thanks, pardon my earlier cynicism... now to post a new problem with the debug heap...

Help for ETSLayoutDialog Manager!

bosfan6-Sep-06 3:27

bosfan

6-Sep-06 3:27

Hello,
can someone help me with this problem in ETSLayoutManager??

thax
break;

Re: Help for ETSLayoutDialog Manager!

Cedric Moonen6-Sep-06 4:05

Cedric Moonen

6-Sep-06 4:05

Err... That's a very clear description of your problem Hmmm | :|

Cédric Moonen
Software developer

Charting control [Updated - v1.1]

Re: Help for ETSLayoutDialog Manager!

bosfan6-Sep-06 4:30

bosfan

6-Sep-06 4:30

Hello Moonen,
sorry :->, ETSLayoutDialog Manager is here in the comunity, a litle framework to manage the dialog items,
mean, when dialog resize, normaly all dlg items stay on the same place, with this framework you can
replace and resize all items!
Here is the url:
http://www.codeproject.com/dialog/layoutmgr.asp

and my try:

<br />
// get pointer to my dialog on the first tabitem:<br />
CMyDialog* pdlg = ((CMyDialog*)m_cTabAll.GetTab(0));<br />
<br />
// now, here, the dialog is resized only in width, not in hight!?<br />
// if i take out this params 0, 0, -125, 0 -> the dialog on the first tab is 3-4cm under the tabs(with tabcaption)!<br />
// so, i set them 125pxls to top!<br />
CPane DIALOG = paneCtrl( pdlg, HORIZONTAL, RELATIVE_VERT, 0,0,-125,0/*613*/)<br />
<< item(pdlg, GREEDY);<br />
<br />
CPane TABCTRL = paneTab(&m_cTabAll,HORIZONTAL, GREEDY)<br />
<< DIALOG<br />
<< itemGrowing(VERTICAL);<br />
<br />
// i thake out the code that is not importend<br />
CreateRoot(VERTICAL)<br />
<< TOOLBAR // pane with toolbar<br />
<< TABCTRL<br />
<< PROGRESS<br />
<< itemGrowing(HORIZONTAL)<br />
<< itemGrowing(HORIZONTAL)<br />
<< item(IDC_STATUSBAR, ABSOLUTE_VERT);<br />
<br />
<br />
UpdateLayout();<br />

hope this is a litle more information!

with best regards
berak;

Re: Help for ETSLayoutDialog Manager!

Cedric Moonen6-Sep-06 4:34

Cedric Moonen

6-Sep-06 4:34

If it comes from an article, then it's better to post in the message board at the bottom of the article if the article doesn't provide enough information.

Cédric Moonen
Software developer

Charting control [Updated - v1.1]

Re: Help for ETSLayoutDialog Manager!

bosfan6-Sep-06 5:09

bosfan

6-Sep-06 5:09

Hi,
yes, that what i think before, but, in this artikle does nobody maintain this posts, they are no answers on questions Frown | :(

!?
Therefore i think maybe is someone in the comunity who use this framework to and so can help me???

regards
break;

MCI CD Audio Output

Cpt Rick6-Sep-06 2:56

Cpt Rick

6-Sep-06 2:56

I built this little CD player for use in one of my apps using standard MCI strings and commands. What I can't figure out, is how to direct the output to a particular sound card.

By default, the output goes to whatever is the primary sound device at the time, but I figure there "must" be a way to redirect it, without changing the default output card.

Anybody do this before?

Re: MCI CD Audio Output

Christopher Duncan6-Sep-06 7:52

Christopher Duncan

6-Sep-06 7:52

Hey, Rick.

I've got some MCI code in an app at the house and I'll be happy to look at it to see if I've fought that battle already. It's been awhile, and I've slept since then. Big Grin | :-D

The tricky part will be remembering to take a look. Send me an email from this post to remind me, and I'll poke around and see if I can help. I seem to recall that you can enumerate the devices. If so, I'll shoot you some code.

Author of
The Career Programmer and Unite the Tribes
www.PracticalStrategyConsulting.com

storing data to a file

vijay_aroli6-Sep-06 1:53

vijay_aroli

6-Sep-06 1:53

hello. i am writing certain data from memory into file on the disk. how can i write the same data into a file on the FTP server??? is the process of writing data to an FTP file is same as that of writing data on to file in the local disk??

vijay

Re: storing data to a file

led mike6-Sep-06 6:07

led mike

6-Sep-06 6:07

http://en.wikipedia.org/wiki/File_Transfer_Protocol[^] Roll eyes | :rolleyes:

"Alot of the people on this forum are incredibly stupid, thinking that the internet is real"
Score: 1.0 in the Soap Box

led mike

Re: storing data to a file

Jun Du6-Sep-06 10:32

Jun Du

6-Sep-06 10:32

There is no such a thing called "FTP file". FTP is a protocol, which is used to transfer data in two formats: ASCII and binary.

Maybe you can clearify a bit about what you wanted? If you write data to the FTP server, which is mapped as mapped network drives on your local machine, then the write is just as you're writing to a local drive.

Best,
Jun

How Can i Call a Function Providing its name as a string

MIAN KAMRAN6-Sep-06 1:29

MIAN KAMRAN

6-Sep-06 1:29

How Can i Call a Function Providing its name as a string in C\C++

Re: How Can i Call a Function Providing its name as a string

Rajesh R Subramanian6-Sep-06 1:36

Rajesh R Subramanian

6-Sep-06 1:36

Name as a string? Can you be more specific? I do not get this question.

Brahmma

According to the laws of aerodynamics, the bumble bee must not be able to fly. The bumble bee does not know aerodynamics. It goes on flying anyway.

Re: How Can i Call a Function Providing its name as a string

Cedric Moonen6-Sep-06 1:38

Cedric Moonen

6-Sep-06 1:38

Simple answer: you can't.

But, why would like to do such a thing ? Provide as much relevant information you can so we can help you to find a better solution (it probably results from a bad design).

Cédric Moonen
Software developer

Charting control [Updated - v1.1]

Re: How Can i Call a Function Providing its name as a string

Frank K6-Sep-06 2:44

Frank K

6-Sep-06 2:44

Hi,

Function as a string?? Why? ... but ...

You can get the address of a function with

<br />
FARPROC GetProcAddress(HMODULE hModule, LPCSTR lpProcName);<br />

You need the module handle and the name of the function.

Example for the function GetMenu from user32.dll

<br />
typedef HMENU (WINAPI *GETMENU) (HWND);<br />
GETMENU FuncGetMenu;<br />
HMODULE hUser32Dll;<br />
<br />
_hUser32Dll = ::LoadLibrary("user32.dll");<br />
if(NULL != hUser32Dll)<br />
{<br />
FuncGetMenu = (GETMENU)::GetProcAddress(hUser32Dll, "GetMenu");<br />
}<br />
<br />
if(NULL != FuncGetMenu)<br />
{<br />
FuncGetMenu(WindowHandle); //HMENU GetMenu(HWND hWnd);<br />
}<br />

This is an example for dynamic load a dll.
--> You need more than only the function name! You also need the function declaration.

HTH
Frank

Re: How Can i Call a Function Providing its name as a string

C^hris L^osinger6-Sep-06 2:54

C^hris L^osinger

6-Sep-06 2:54

you can't, not directly anyway.

but, you could create a map that maps strings (names) to function pointers.

image processing | blogging

Re: How Can i Call a Function Providing its name as a string

Viorel.6-Sep-06 3:12

Viorel.

6-Sep-06 3:12

The next sample for Visual Studio 2005 uses map and function pointers:

#include "stdafx.h"
#include "math.h"
#include <map>
#include <string>

void main()
{
	using namespace std;

	typedef double (* FUNCTION_POINTER)(double);

	// make the map

	map< string, FUNCTION_POINTER > functions;

	functions["sin"] = sin;
	functions["cos"] = cos;
	functions["tg"] = tan;

	// test: call a function by name

	std::string name;

	name = "cos";

	FUNCTION_POINTER function = functions[name];

	double result = function(1.2);

}

I hope it works and gives you some ideas.

Re: How Can i Call a Function Providing its name as a string

yjzh6-Sep-06 4:20

yjzh

6-Sep-06 4:20

a piece of cake, function pointer or functors can do this.

boost

Re: How Can i Call a Function Providing its name as a string

Rilhas8-Sep-06 9:29

Rilhas

8-Sep-06 9:29

Complementing to the other answers already given, the quick answer would be no, at least not in the way BASIC (for example) lets you do it (something like execute("a=myfunc(10,20)").

The process of calling functions based on the contents of a string has to be manually coded in some way. The most "automatic" way is the already mentioned "GetProcAddress" (you can hide most of the steps required inside macros or in a general purpose function), but prototypes will be always a pain (unless if they are, trivially, the same).

Depending on the extent of work you are willing to do, you can go as far as building your own C/C++ interpreter. I did this once, for a home automation system, where I made a program to go through all of my header files, scan function names and prototypes, and write code to execute the correct function with the correct parameters based on the contents of a string (the command entered by the user). Is not very hard work if you control the classes and functions. If not then be prepared for trouble.

I hope this helps,
Rilhas

Winsock TCP Client disconnect

Eytukan6-Sep-06 1:21

Eytukan

6-Sep-06 1:21

I have a question.
Are these same?

1. Close the client application window. [ Closes the stream ],
(Server gets out of the below block)

<br />
do<br />
{<br />
n=recv(client,buff,MAX_BUFF_SIZE,0);<br />
 if(n==SOCKET_ERROR )	<br />
  {<br />
   break;<br />
  }<br />
}while()<br />

2. UnPlug the client's network cable. [should close the stream?] ,
server never gets notified? it never happens. WTF??? WTF | :WTF:

I'm not able to detect the latter one. Please help. If the n/w cable is unplugged, the stream would be broken and it should fire a sock exception right? Unsure | :~

<marquee scrollamount="1" scrolldelay="1" direction="up" height="10" step="1">--[ Jig | [Dance]

]--

[My Current Status]

Link2006 wrote:Let's take it outside of CP
Jeremy : Please don't.I would love to see this.I'm making the popcorn already.

Re: Winsock TCP Client disconnect

Frank K6-Sep-06 2:29

Frank K

6-Sep-06 2:29

Hi,

the value from SOCKET_ERROR is -1
if you unplug the network recv will be return 0

Change your code to

<br />
do<br />
{<br />
n=recv(client,buff,MAX_BUFF_SIZE,0);<br />
if(1 > n)<br />
{<br />
break;<br />
}<br />
}while();<br />

HTH
Frank

Re: Winsock TCP Client disconnect

Eytukan6-Sep-06 3:17

Eytukan

6-Sep-06 3:17

Nope!

It doesn't work. The disconnection is not detected. Please help.

<marquee scrollamount="1" scrolldelay="1" direction="up" height="10" step="1">--[ Jig | [Dance]

]--

[My Current Status]

Link2006 wrote:Let's take it outside of CP
Jeremy : Please don't.I would love to see this.I'm making the popcorn already.

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