blocking processes - C / C++ / MFC Discussion Boards

cberam14-May-04 19:38

14-May-04 19:38

Hi,

In my server application in VC++,i create and execute a particular process .
when this process is running,i want to excute another process as background without
interupting the current process.How do acheive this.If to use CreateProcess()
then how to get it.Pls help

If createprocess needs to be in separate thread ,then how to acheive this.
Pls can anyone get me some sample code snippets for this.

Thnks in advance
Ram

Re: Background Process

22491714-May-04 22:01

224917

14-May-04 22:01

cberam wrote:
If createprocess needs to be in separate thread ,then how to acheive this.

There is no need for any separate thread to use CreateProcess(); It will return immediately after creating the new process.

check following:
A newbie's elementary guide to spawning processes
[^]

It's not a bug, it's an undocumented feature.
suhredayan@omniquad.com

messenger :suhredayan@hotmail.com

Re: Background Process

cberam16-May-04 18:03

cberam

16-May-04 18:03

Hi,

Thanks for the reply.When the "CreateProcess" is invoked,the current process is interrupted for few seconds.which i don't want to happen.That's why i want to start
in a separate thread or as a background process.Pls do help

Thnks in advance

Ram

Combo box limit

Anonymous14-May-04 18:47

Anonymous

14-May-04 18:47

Greetings!

What is the maximum limit of the number of items we can insert in combo box. How can i retrieve or increase this limit ?

Re: Combo box limit

Michael Dunn14-May-04 20:10

Michael Dunn

14-May-04 20:10

Combo boxes use an integer to index the items, so the theoretical limit is 2GB-1. You'll run out of memory before you hit that limit, though. And on 9x, due to 16-bit limitations, the actual limit is 32767.

--Mike--
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loan calculator

felix joe14-May-04 18:42

felix joe

14-May-04 18:42

hi, anyone knows how to do a program to calculate loan using MFC when user inputs loan term, interest rate, and downpayment?
Thanks.

felix joe

Re: loan calculator

toxcct15-May-04 0:37

toxcct

15-May-04 0:37

having a look at CP articles can help you much than asking suxh questions...

watch this : http://www.codeproject.com/cpp/loan.asp[^]

(i don't know at all what is the loan calculator, so i hope that will help, anyway, there was many articles when i searched for it, so i think if this doesn't satisfy you, you could search by yourself).

TOXCCT >>> GEII power

blocking processes

kanetheterrible114-May-04 18:41

kanetheterrible1

14-May-04 18:41

hi !
Does anybody know how to stop a process without killing it ?
What i needed was that my program hooked windows and get notification when explorer or any other windows component calls FindFirstFile(...)
my application gets a notification message.Now based on certain settings my program must allow FindFirstFile(...) to execute ,or prevent it from execution.I have proceeded till the notification part.Currently the app is notified when FindFirstFile(...) is called.But how do i stop it?
Also the app must be cross platform friendly ...and i don't have DDK so the solution can't be driver based...

Kane Smile | :)

Some guys hack just to get themselves a girlfriend.What a pathetic reason huh?

Re: blocking processes

Alexander ^M.,16-May-04 1:23

Alexander ^M.,

16-May-04 1:23

fetch the thread list and suspend all of them.

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

blocking processes

kanetheterrible114-May-04 18:39

kanetheterrible1

14-May-04 18:39

Constrol bar and splitters

alex.barylski14-May-04 18:37

alex.barylski

14-May-04 18:37

How can I make a control bar float and dock inside a pane of a CSplitterWnd instead of the CMainFrame???

Doc I have to override CMainFrame DockControlBar() or something?

Thanks Smile | :)

How do I print my voice mail?

Assigning a value to a static char array

monrobot1314-May-04 17:50

monrobot13

14-May-04 17:50

I thought I knew what I was doing, but I can't come up with any way to initialize my static character array. It's defined, in the header file as

static char var[4];

In my source file I have tried every way I know of to give it a value to no avail. Any help is appreciated as I'm sure it can be done, I obviously have no idea how though.

- Aaron

Re: Assigning a value to a static char array

nguyenvhn14-May-04 18:00

nguyenvhn

14-May-04 18:00

I am afraid that I would not really understand your idea. But I give you here an example, it may help you.

<br />
class X{<br />
public:<br />
...<br />
private:<br />
  ....<br />
  static char st[4];<br />
  ....<br />
};<br />
<br />
char X::st[4]="123";<br />
static char ss[4]="abc";<br />
....<br />

Re: Assigning a value to a static char array

Michael Dunn14-May-04 20:13

Michael Dunn

14-May-04 20:13

You normally don't put a static global variable in a header file; the purpose of using such a global is to restrict its visibility to one .CPP file.
You can give it an initial value in the .CPP file like so:

static char var[4] = "abc";

--Mike--
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Accessing distant database from a program?

__Cerb14-May-04 15:42

__Cerb

14-May-04 15:42

How would that be possible? I would like to access a MySQL database on my site from a program.

Thanks.

Michael

Re: Accessing distant database from a program?

nguyenvhn14-May-04 18:04

nguyenvhn

14-May-04 18:04

I have not done that before, but I think you could use ODBC, ADO with MySQL driver for Windows. I've ever used MySQL driver for ODBC to import mySQL data into MS Access.

#include nightmare

Ernesto D.14-May-04 13:39

Ernesto D.

14-May-04 13:39

Hi all, whenever i need some symbols/constants to be avairable to my entire application (all its files i mean), i create a header file (appconsts.h), and i #include it in each .cpp file of my application. this always worked fine, till recently, i recived some advice to stop using macros (#define) to define constants, and started using const, so (in my current project) i happily went to my appconsts.h file, and changed it like this (an example):

Before:
#if !defined(APPCONSTS_H)
#define APPCONSTS_H

#define MY_STRING _T("a string")
#define MY_NUMBER 100
enum MY_ENUM{En1=0, En2, En3};

#endif

AFTER:

#if !defined(APPCONSTS_H)
#define APPCONSTS_H

const TCHAR* MY_STRING = _T("a string");
const int MY_NUMBER = 100;
enum MY_ENUM{En1=0, En2, En3};

#endif

its all very nice, the only problem is that i now get 708 errors (yes 708), about MY_STRING and MY_NUMBER allready being defined in another object. for example:
ClientEditDlg.obj : error LNK2005: "char const * const COLHT_VLV_NOTES" (?COLHT_VLV_NOTES@@3PBDB) already defined in Boletaje.obj

onfigSheet.obj : error LNK2005: "char const * const IF_FILENAME" (?IF_FILENAME@@3PBDB) already defined in Boletaje.obj

please notice that i DID include guards on the appconsts.h file, i tried removing all the #includes to appconsts.h file, and just including it in my stdafx.h file, but no luck, and since this is a WTL project, i dont have any other file (besides stdafx.h) that gets included everywhere.
Can someone help me out?

***UPDATE***
mhh, i get it now, i should declare the consts in some .cpp file (say where my winmain()is), and then op appconsts.h i should do like this:

extern const TCHAR* MY_STRING = _T("a string");
extern const int MY_NUMBER = 100;
enum MY_ENUM{En1=0, En2, En3};

is this correct?
if so, wouldnt be easyer to just use #define instead of const? i mean, MS uses it! for example in winuser.h:
// ShowWindow() Commands
#define SW_HIDE 0
#define SW_SHOWNORMAL 1
#define SW_NORMAL 1
#define SW_SHOWMINIMIZED 2
#define SW_SHOWMAXIMIZED 3
#define SW_MAXIMIZE 3
...

what you guys think?

Re: #include nightmare

Michael Dunn14-May-04 13:44

Michael Dunn

14-May-04 13:44

When you change to consts, you are creating global variables. As such, you have to declare/define them differently.
What's happening now is that a.cpp includes appconsts.h and sees MY_STRING is a global variable, so MY_STRING (appropriately name-decorated) goes into a.obj.
Then b.cpp comes along, includes appconsts.h, and sees MY_STRING. Same thing happens, MY_STRING goes into b.obj.
When the linker runs, it collects the obj files into an executable, but sees the multiple definitions of MY_STRING, which breaks the ODR (one definition rule: each symbol must have exactly one definition).

For a quick hack, add __declspec(selectany) to the variable definitions. The real way to solve it is in the FAQ[^]

--Mike--
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Re: #include nightmare

Ernesto D.14-May-04 13:50

Ernesto D.

14-May-04 13:50

Thanks for your answer Michael, i updated the original message before i readed your reply (i guess i was updating it while you were adding the reply Smile | :)

, i would appreciate if you read the update and tell me what you think about using #define

Re: #include nightmare

Michael Dunn14-May-04 14:04

Michael Dunn

14-May-04 14:04

That's still not exactly right. You don't initialize global variables in the header file, but in the .cpp file where they are defined.

appconsts.h:
extern TCHAR* FOO;

appconsts.cpp:
TCHAR* FOO = _T("Hello");

The Windows headers use #define because the API is still a C interface, and const is not supported by all C compilers (it was officially added to C rather recently).

--Mike--
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Re: #include nightmare

Ernesto D.14-May-04 15:23

Ernesto D.

14-May-04 15:23

Thanks Mike Smile | :)

i need help with CopyFile

Ryan McDermott14-May-04 12:50

Ryan McDermott

14-May-04 12:50

I need source code to a program that copies itself into a certain directory like "C:\Program Files" and I want it to have a list of certain names. I got this so far:

void main()
{
char *filenames[] = {"information.exe", "test.exe", "testing.exe"

};

LPCTSTR Destination = ("C:\\Program Files\\");
CopyFile(ModuleFileName, Destination);
}

but I don't know how to copy itself as those filenames.

-Ryan M.

Re: i need help with CopyFile

Anonymous14-May-04 13:46

Anonymous

14-May-04 13:46

Sounds like a really amateur virus
Anyway You should issue a call for each name in the filenames
and your void main shouldn't end with a ;

to copy a file you have several options:
i would go for a while (fread()) fwrite style
or even an assembly copy

How to response WM_LBUTTONDBLCLK in the MDIClient area?

huyoo14-May-04 11:56

huyoo

14-May-04 11:56

Inorder to catch WM_LBUTTTONDBLCLK in MDIClient area I do that:
1.

BOOL CMainFrame::PreCreateWindow(CREATESTRUCT& cs)<br />
{<br />
	if( !CMDIFrameWnd::PreCreateWindow(cs) )<br />
		return FALSE;<br />
	return TRUE;<br />
}

added
cs.style|=CS_DBLCLKS;//to response DoubleClick
2.reload PreTranslateMessage(MSG* pMsg)Function:

BOOL CMainFrame::PreTranslateMessage(MSG* pMsg) <br />
{<br />
      //if(pMsg->hwnd==m_hWndMDIClient && pMsg->message==WM_LBUTTONDOWN)<br />
	//PostMessage(WM_LBUTTONDOWN);<br />
<br />
<br />
       if(pMsg->hwnd==m_hWndMDIClient && pMsg->message==WM_LBUTTONDBLCLK)<br />
	PostMessage(WM_LBUTTONDBLCLK);<br />
     return CMDIFrameWnd::PreTranslateMessage(pMsg);<br />
}

3.in CMainFrame add
WM_LBUTTONDOWN AND WM_LBUTTONDBLCLK Message_map:

void CMainFrame::OnLButtonDown(UINT nFlags, CPoint point) <br />
{<br />
	AfxMessageBox("Left Mouse Down!");<br />
	CMDIFrameWnd::OnLButtonDblClk(nFlags, point);<br />
}<br />
void CMainFrame::OnLButtonDblClk(UINT nFlags, CPoint point) <br />
{<br />
	AfxMessageBox("Left Mouse DoubleClicked!");<br />
	CMDIFrameWnd::OnLButtonDblClk(nFlags, point);<br />
}

:(but all that did'nt work,none messagebox OUT!!

WHY ?????? Confused | :confused:

i wanna learn more @_@!

Re: How to response WM_LBUTTONDBLCLK in the MDIClient area?

huyoo15-May-04 6:49

huyoo

15-May-04 6:49

Pls help me !

Is there anyone can help me?

sos!!

i wanna learn more @_@!

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