VC++ Basic Threading - help - C / C++ / MFC Discussion Boards

Re: help me to cut a CString to many pieces

David Crow9-Sep-09 10:57

David Crow

9-Sep-09 10:57

There's also AfxExtractSubString().

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Re: help me to cut a CString to many pieces

Joe Woodbury9-Sep-09 13:03

Joe Woodbury

9-Sep-09 13:03

Base 10 conversion is so simple, just write your own quick parser to walk the string and convert each chunk at the same time.

FeeEnterView.obj : error LNK2019: unresolved external symbol "public: __thiscall ATL::CTime::CTime(void)" [modified]

Vetukuri Raju9-Sep-09 4:55

Vetukuri Raju

9-Sep-09 4:55

hi vc++ programmers,,
i am getting the following errors in migrating my code from vs-2--3 to vs-2008...
FeeEnterView.obj : error LNK2019: unresolved external symbol "public: __thiscall ATL::CTime::CTime(void)"
and

fwstissr.obj : error LNK2001: unresolved external symbol ___security_cookie

can enbody show a remedy for this....thanks in advance

modified on Wednesday, September 9, 2009 11:04 AM

Accessing files which are in JAR

Azghar Hussain9-Sep-09 2:50

Azghar Hussain

9-Sep-09 2:50

Hi,

I have couple of text files in JAR. I want to access them in my C++ application. Basically I want to get the FILE pointer to those file. Please let me know how would we do it.

thanks in advance

Umrahi...

If you have faith in the cause and
the means and in God, the hot
Sun will be cool for you.

Re: Accessing files which are in JAR

David Crow9-Sep-09 3:16

David Crow

9-Sep-09 3:16

See here for ideas.

Re: Accessing files which are in JAR

CPallini9-Sep-09 3:20

CPallini

9-Sep-09 3:20

Why don't you use the jar tool to decompress the files?
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

[My articles]

Re: Accessing files which are in JAR

Michael Schubert9-Sep-09 21:20

Michael Schubert

9-Sep-09 21:20

Judging from the header, they are simple ZIP files. Try one of the ZIP/UNZIP classes here on CP to access them.

VC++ Basic Threading - help

GC1049-Sep-09 1:31

GC104

9-Sep-09 1:31

I am creating a vs2005 vc++ application and trying to get a secondary thread setup and working. I have read through the various postings and tried to put some code together but it won't compile.

I am trying to start the new thread from a menu item via a message handler based in my application's 'CView' based class. I have created a new class of my own (GcWorkerThread) and is derived from CWinThread, and contains a member function 'GcThreadFunction'

calling code:

int x;
CWinThread *pThread = AfxBeginThread (GcThreadFunction, x);

UINT GcWorkerThread::GcThreadFunction (LPVOID pParam)
{
 int t;
 for (int y=0; y&lt;1000000; y++
 {
 }

}

When is comes to compiling the code I get an error:
"Error C3867 'GcWorkerThread::GcThreadFunction' function call missing argument list
use &GcWorkerThread::GcThreadFunction to create a pointer to member"

What am I doing wrong?
Frown | :(

Re: VC++ Basic Threading - help

CPallini9-Sep-09 1:59

CPallini

9-Sep-09 1:59

You cannot pass a instance method to AfxBeginThread. You've to pass a standard function or a class (i.e. static) method.
BTW: have a look at this [^].
Smile | :)

Re: VC++ Basic Threading - help

Selvam R9-Sep-09 2:11

Selvam R

9-Sep-09 2:11

try with the following change.

int x;
CWinThread *pThread = AfxBeginThread (GcThreadFunction, &x);

Thanks and Regards,
Selvam,
http://www.wincpp.com

Re: VC++ Basic Threading - help [Updated]

Nuri Ismail9-Sep-09 2:28

Nuri Ismail

9-Sep-09 2:28

GC104 wrote:
I have read through the various postings and tried to put some code together but it won't compile.

Instead of reading through the various postings I can suggest reading this[^] useful article about worker threads.

[edit] Sorry I didn't see that CPallini have already gave this link Sigh | :sigh:

[\edit]

Regards
Nuri Ismail

Re: VC++ Basic Threading - help

GC1049-Sep-09 4:12

GC104

9-Sep-09 4:12

Info gratefully received, I have gone away and think I now have a better understanding of what a 'static member function' is all about. However I'm struggling with the example given on the link given. see below:

static UINT run(LPVOID p);
void run();
volatile BOOL running;
To start a thread, your handler does

void CMyView::doInvert()
    {
     running = TRUE;
     AfxBeginThread(run, this); // why is a 'this' pointer passed as the pParam?
                                // run is refering to member function 'UINT CMyView::run(LPVOID p)'?
    }
 
UINT CMyView::run(LPVOID p)
    {
     CMyView * me = (CMyView *)p;  //why is 'p' cast from something that already seems to be 
                                   //a CMyView pointer already?
     me -> run();
     return 0;
    }
 
void CMyView::run()  //run is an overloaded function?
   {
     for(int x=y = 0; running && y < image.height; y++)
          for(int x = 0; running && x < image.width; x++)
              changePixel(x, y);
    running = FALSE;
   }

Re: VC++ Basic Threading - help

Cedric Moonen9-Sep-09 4:20

Cedric Moonen

9-Sep-09 4:20

// why is a 'this' pointer passed as the pParam?

Because of what static functions implies: a static function is shared among all instances of a class. This means that within a static function, you cannot access non-static members of the class. In order to be able to do so, you need to identify which instance you want to manipulate. This is the reason why you pass the instance as a parameter to the thread function.In fact, a static function is similar to a global function in this context.

//why is 'p' cast from something that already seems to be
//a CMyView pointer already?

Because it is received as a LPVOID, which doesn't mean anything. So, to be able to call the Run function on the instance, the compiler needs to know that it is a CMyView object (it can't guess it).

Cédric Moonen
Software developer

Charting control [v2.0]
OpenGL game tutorial in C++

Re: VC++ Basic Threading - help

Rajesh R Subramanian9-Sep-09 6:07

Rajesh R Subramanian

9-Sep-09 6:07

Just adding to the previous reply

GC104 wrote:
// why is a 'this' pointer passed as the pParam?

Because inside the worker thread, a CMyView object is being manipulated (in this case). This particular thread function needs a CMyView object be passed to it.

Note: However, it would be a lot better if threads can accept any object (or data type) passed as the parameter in general. Because different threads do different things. Some threads won't require anything at all. Therefore, the best approach would be to pass a pointer to "something". And this something is known to the calling code (it sets up the parameter) and the thread also know what exactly is the pointer pointing to and so you cast it to the appropriate type.

GC104 wrote:
//why is 'p' cast from something that already seems to be

p is a pointer to void (remember that LPVOID is nothing but void *). Therefore, you must cast it to an appropriate type (read my note above?)

Hope that helps. Smile | :)

It is a crappy thing, but it's life -^ Carlo Pallini

Re: VC++ Basic Threading - help

GC10410-Sep-09 23:01

GC104

10-Sep-09 23:01

Many thanks for help given, I now have a basic 'thread' the compiles and does roughly what I expect Smile | :)

How do I rename Outlook Pst newly created folder 'Personal Folders' programmatically ?

SherTeks9-Sep-09 0:54

SherTeks

9-Sep-09 0:54

Hi All,

How do I rename a newly created pst folder 'Personal Folders'
in Microsoft Outlook programmatically.

Any script (vb OR VC++ COM, automation, etc.) or a bit of
guidance would be helpful

Thanks in Advance

Re: How do I rename Outlook Pst newly created folder 'Personal Folders' programmatically ?

Selvam R9-Sep-09 1:22

Selvam R

9-Sep-09 1:22

http://support.microsoft.com/kb/180232[^]

Thanks and Regards,
Selvam,
http://www.wincpp.com

Re: How do I rename Outlook Pst newly created folder 'Personal Folders' programmatically ?

Adam Roderick J9-Sep-09 1:31

Adam Roderick J

9-Sep-09 1:31

Just refer [^]

Величие не Бога может быть недооценена.

how to create conference with iaxclient.dll?

nitu dhanurved9-Sep-09 0:48

nitu dhanurved

9-Sep-09 0:48

hello all,

I am using iaxclient.dll for making IAX based soft-phone.I wanted to create conference with this dll. Can anyone suggest me how to use this dll for creating a conference??????

Regards
New_bie

Re: how to create conference with iaxclient.dll?

Adam Roderick J9-Sep-09 2:09

Adam Roderick J

9-Sep-09 2:09

make the question in details to get answer, otherwise no will answer it, since this information is too little to understand Roll eyes | :rolleyes:

Величие не Бога может быть недооценена.

Re: how to create conference with iaxclient.dll?

Richard MacCutchan9-Sep-09 3:07

Richard MacCutchan

9-Sep-09 3:07

Have you checked the iaxclient documentation?

CVTRES : fatal error CVT1100: duplicate resource. type:DIALOG, name:PRINTSTATUS, language:0x0409

Vetukuri Raju8-Sep-09 23:40

Vetukuri Raju

8-Sep-09 23:40

hi all,
I am getting the following error when i am converting my project from vs-2003 to vs-2008.
CVTRES : fatal error CVT1100: duplicate resource. type:DIALOG, name:PRINTSTATUS, language:0x0409
But i dont have an id for my dialog...if i keep an id then i am getting more linking errors...can anybody help,,,thanks in advance

Re: CVTRES : fatal error CVT1100: duplicate resource. type:DIALOG, name:PRINTSTATUS, language:0x0409

Adam Roderick J9-Sep-09 0:02

Adam Roderick J

9-Sep-09 0:02

can you check resource.h for duplicate resource IDs.

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Re: CVTRES : fatal error CVT1100: duplicate resource. type:DIALOG, name:PRINTSTATUS, language:0x0409

Vetukuri Raju9-Sep-09 0:20

Vetukuri Raju

9-Sep-09 0:20

Hi
But in my resource.h,i dont have an id for this dialog even,even though i dont have an id for this dialog i am getting ths error..

Re: CVTRES : fatal error CVT1100: duplicate resource. type:DIALOG, name:PRINTSTATUS, language:0x0409

Adam Roderick J9-Sep-09 0:32

Adam Roderick J

9-Sep-09 0:32

so not even a single duplicated ID in that resource.h?

if not then disable incremental linking.

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