Re: Not able to navigate data between vc++ project and USB device. - C / C++ / MFC Discussion Boards

Paul Ranson13-Apr-04 2:03

13-Apr-04 2:03

I recommend you use a more modern design of container, perhaps std::vector<unsigned char>. These containers provide a copy constructor so that the compiler default copy constructor for your class will work.

I don't think you should be having to work out how to copy a CByteArray efficiently, or even correctly.

Paul

How can stor a listbox strings with serialization?

Mehdi_Hosseinpour12-Apr-04 2:59

Mehdi_Hosseinpour

12-Apr-04 2:59

I want to store listbox strings in to a file with serialization and load strings from this file with serialization.

Mehdi Hosseinpour

Re: How can stor a listbox strings with serialization?

David Crow12-Apr-04 3:39

David Crow

12-Apr-04 3:39

Something like:

CString str;
CFile file;
file.Open(..., CFile::modeWrite);
CArchive ar(&file, CArchive::store);
for (int x = 0; x < listbox.GetCount(); x++)
{
    listbox.GetText(x, str);
    ar << str;
}
ar.Close();
file.Close();

"The pointy end goes in the other man." - Antonio Banderas (Zorro, 1998)

Re: How can stor a listbox strings with serialization?

Ravi Bhavnani12-Apr-04 9:10

Ravi Bhavnani

12-Apr-04 9:10

Might want to ar << listbox.GetCount(); first. Smile | :)

/ravi

My new year's resolution: 2048 x 1536
Home | Articles | Freeware | Music
ravib@ravib.com

Re: How can stor a listbox strings with serialization?

David Crow12-Apr-04 9:13

David Crow

12-Apr-04 9:13

Of course. I never indicated it was a complete working code example, hence the "Something like" qualifier. When typing this stuff from memory, small details often get omitted.

"The pointy end goes in the other man." - Antonio Banderas (Zorro, 1998)

Re: How can stor a listbox strings with serialization?

Ravi Bhavnani12-Apr-04 9:09

Ravi Bhavnani

12-Apr-04 9:09

See this[^] series of articles.

/ravi

My new year's resolution: 2048 x 1536
Home | Articles | Freeware | Music
ravib@ravib.com

Not able to navigate data between vc++ project and USB device.

Pankaj Bhalla12-Apr-04 2:59

Pankaj Bhalla

12-Apr-04 2:59

Hi All.

The problem I am facing is a bit different. Even I do not know, whether the problem is related to Embedded programming or can be solved with VC++ MFC itself.

I want to send and recieve data between my vc++ application and a USB device. Thats the main issue.

Can anyone tell from where to start or if anyone can help me with the coding that should be done...I will be very thankfull for that help.

Thanks and regards,

Pankaj Bhalla
pankajbhalla@mantraonline.com

Pankaj Bhalla
Consultant - VC++

Re: Not able to navigate data between vc++ project and USB device.

Darshan Jani12-Apr-04 7:21

Darshan Jani

12-Apr-04 7:21

Which USB Device you are talking about.
Please Clarify.

Re: Not able to navigate data between vc++ project and USB device.

Pankaj Bhalla13-Apr-04 0:15

Pankaj Bhalla

13-Apr-04 0:15

Hello Darshan.

Thanks for your consideration and time. Actually, the USB device is itself, under the process of creation. So, not sure about the device, but if you can then please tell me general steps we have to take to make it possible. I mean the articles or any other source from where I can get more information about this issue. If you can the please tell me the MFC classes we can use or any info. about MFC and USB devices.

Thanks and Regards,

Pankaj Bhalla

GDI

Ni@m12-Apr-04 2:42

Ni@m

12-Apr-04 2:42

Where can I download GDI+ librarys and headers?

Re: GDI

Indrawati12-Apr-04 2:50

Indrawati

12-Apr-04 2:50

You can get it from:

http://www.microsoft.com/msdownload/platformsdk/sdkupdate/

I think it's in the core SDK part.

freeing memory for an array

kfaday12-Apr-04 2:38

kfaday

12-Apr-04 2:38

I've got a char array

<br />
char *vec;<br />

and i allocate memory for a number of elemets

<br />
vec = (char*) malloc ((sizeof(char))*(number_of_elemets));<br />

i do that in main.
then i call a free function

<br />
free_mem (vec);<br />

the function code is:

<br />
void free_mem (char *vec,number_of _elements)<br />
{   <br />
        for (i=0;i<(number_of _elements);i++)<br />
	{<br />
                 	free (vec[i]);<br />
	}<br />
}<br />

it gives me errors
what's wrong?
thanks!!

Re: freeing memory for an array

Anonymous12-Apr-04 2:45

Anonymous

12-Apr-04 2:45

try this:

char *vec;
vec = new char[number_of_elements];

Re: freeing memory for an array

kfaday12-Apr-04 2:49

kfaday

12-Apr-04 2:49

it's only ansi c, i can't use c++

Re: freeing memory for an array

Indrawati12-Apr-04 2:53

Indrawati

12-Apr-04 2:53

I think you can just use free(vec), not free(vec[i]). Or maybe the error occurs because you forgot to pass the number_of_elements argument when you call free_mem?

Re: freeing memory for an array

David Crow12-Apr-04 3:43

David Crow

12-Apr-04 3:43

Indrawati wrote:
I think you can just use free(vec)...

Correct.

"The pointy end goes in the other man." - Antonio Banderas (Zorro, 1998)

Dependency Walker lists a DLL as missing. However, program works without Error. Why?

Tony Westminster12-Apr-04 2:26

Tony Westminster

12-Apr-04 2:26

Hello,

I compiled a program that reads the MAC-Adapter information and
therefore requires IPHLPAPI.DLL.

Now, on XPPro it's fine. DependencyWalker shows EFSADU.DLL to be
present in C:\windows\sytem32.

On XPHome, DependencyWalker shows this file as missing.

However, the program also runs on XP Home without any problems.

Now my question: Should I not care about the DependencyWalker warning
on XPHome? But then, why does this warning come up?
Could it be that DependencyWalker lists DLLs as missing although in reality they are never called (and therefore my app also works on XPHome)?

This is the dependency of the mentioned EFSADU.DLL:

IPHLPAP.DLL->MPRAPI.DLL->SETUPAPI.DLL->SHELL32.DLL->EFSADU.DLL

Thanks in advance for any help,
Tony

Re: Dependency Walker lists a DLL as missing. However, program works without Error. Why?

David Crow12-Apr-04 3:47

David Crow

12-Apr-04 3:47

The Depends utility does not show DLLs that are explicitly linked. It only shows those that are implicitly linked.

"The pointy end goes in the other man." - Antonio Banderas (Zorro, 1998)

Re: Dependency Walker lists a DLL as missing. However, program works without Error. Why?

Tony Westminster12-Apr-04 3:55

Tony Westminster

12-Apr-04 3:55

David,

thanks a lot for that information.

Do you know any way (or tool) that shows only explicitly linked
DLLs?

Thank you,
Tony

Re: Dependency Walker lists a DLL as missing. However, program works without Error. Why?

David Crow12-Apr-04 4:01

David Crow

12-Apr-04 4:01

Try Process Explorer or ListDlls.

"The pointy end goes in the other man." - Antonio Banderas (Zorro, 1998)

Re: Dependency Walker lists a DLL as missing. However, program works without Error. Why?

Tony Westminster12-Apr-04 4:35

Tony Westminster

12-Apr-04 4:35

Thank you very much.

I used Process Explorer and it clearly shows that my app uses
iphlpapi.dll but does NOT use EFSADU.DLL which was listed by
DependencyWalker as not present on XP Home.

I must say that I have never heard about implicitly and explicitly
linked DLLs but assume it means that some DLLs are never used although they might be imported in header files (those would be the implicit ones).

So I think, to know which DLLs I have to include when I want to
distribute my app, I have to do the following:

1) Run the app.

2) Use Process Explorer to see which DLLs it really uses.
I guess I would have to do this in different usage scenarios.
I have no clue how DLLs are loaded into memory, but could it
be the case, that some DLLs are loaded only after the App has started
(I mean until their functionalities are really needed by the app)?
Then this would mean I would have to run ProcessExplorer a few
times while I play around with the app to see if additional DLLs
are loaded.

3) Think about which DLLs are normally present on user's installations of Windows and add those that are likely not to
be present. I still regard this to be a hard thing since one
can never know what the user has and has not installed. Someone
was so kind and enlighten me a bit about this in another thread.

Thanks again for the answers, also to Prakash. Codeproject is a wonderful treasure of knowledge and helpfulness and I hope to give back some day when I have learned enough to do so.

Tony

Re: Dependency Walker lists a DLL as missing. However, program works without Error. Why?

David Crow12-Apr-04 5:15

David Crow

12-Apr-04 5:15

Tony Westminster wrote:
could it be the case, that some DLLs are loaded only after the App has started

Yes, this is what LoadLibrary() and GetProcAddress() are for.

"The pointy end goes in the other man." - Antonio Banderas (Zorro, 1998)

Re: Dependency Walker lists a DLL as missing. However, program works without Error. Why?

Prakash Nadar12-Apr-04 4:01

Prakash Nadar

12-Apr-04 4:01

I dont think its possible to determine explicitly linked dlls, may be if you look into the exe file using some hex viewer software and search for dll you can find all the dlls that are linked explicitly and implicitly..

but then it also has some limitation for example, the utility regsvr32 loads the dll dynamically and the input dll is a parameter, here you can never determine which dll it is loading dynamically.

Re: Dependency Walker lists a DLL as missing. However, program works without Error. Why?

Tim Smith12-Apr-04 6:26

Tim Smith

12-Apr-04 6:26

This is a warning about a DLL an operating system DLL uses. That operating system DLL is smart enough to not load the DLL if it isn't present. It uses the delay loaded DLL system to do this.

Tim Smith

I'm going to patent thought. I have yet to see any prior art.

Newbie GDI question

Indrawati12-Apr-04 2:21

Indrawati

12-Apr-04 2:21

Hi I currently want to use a function which takes in a BITMAPINFOHEADER as its argument. The problem is, I have to obtain it from a bmp file, and I don't know how I can obtain BITMAPINFOHEADER structure from the file.

I know I can use LoadImage function to load a bmp file, but as far as I know, in this case its return value is an HBITMAP handle, which is used to create a CBitmap object. I also know that we can specify the LR_CREATEDIBSECTION flag when we call LoadImage, although frankly speaking I am still unsure what it does. Is there a way to get BITMAPINFOHEADER from CBitmap? Or should I go take another route to get the BITMAPINFOHEADER?

Thanks!

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