Buffer data size - C / C++ / MFC Discussion Boards

Re: Help with double pointers and const

CPallini9-Apr-15 8:52

CPallini

9-Apr-15 8:52

Your are welcome.

Re: Help with double pointers and const

Stefan_Lang10-Apr-15 0:27

Stefan_Lang

10-Apr-15 0:27

The two consts are duplicate. Both refer to the CARPIC value. Neither refers to the pointer.

You might also want to check out my comment to CPallinis response in this thread.

GOTOs are a bit like wire coat hangers: they tend to breed in the darkness, such that where there once were few, eventually there are many, and the program's architecture collapses beneath them. (Fran Poretto)

Re: Help with double pointers and const

Stefan_Lang10-Apr-15 0:14

Stefan_Lang

10-Apr-15 0:14

These second consts don't appear to make sense: both refer to the CARPIC value, neither refers to the pointer holding the address. That's also what my compiler states (in a warning).

To give some examples:

C++

const int *a; // pointer to const int
int const *a; // pointer to const int (same as above!)
const int const *a; // warning C4114: same type qualifier used more than once
int *const a; // const pointer to int
const int * const a; // const pointer to const int

Re: Help with double pointers and const

CPallini10-Apr-15 5:16

CPallini

10-Apr-15 5:16

Yes, you are right.

recovering storage

Member 115916078-Apr-15 9:24

Member 11591607

8-Apr-15 9:24

How do I recover what's left of a file that has been deleted but not completely over written?

Let's say the deleted file is 10mb
5 of those have been overwritten
I want to restore the remaining 5.
Thanks!

Re: recovering storage

Richard MacCutchan8-Apr-15 20:20

Richard MacCutchan

8-Apr-15 20:20

Use Google to find a free application to do it. It is a complex process and requires a detailed understanding of the filesystem where the file was created.

[Repost]

Sascha Lefèvre8-Apr-15 20:33

Sascha Lefèvre

8-Apr-15 20:33

Please don't post in multiple places.
Reclaiming leftover storage[^]
http://www.codeproject.com/Messages/5037564/Storage.aspx[^]

Buffer data size

_Flaviu7-Apr-15 21:46

_Flaviu

7-Apr-15 21:46

Hi all. I have a doubt: how ulSize data buffer size should be:

C++

CString sValue;
ULONG ulSize = _MAX_PATH;
lRet = RegQueryValueEx(hKey, NULL, NULL, NULL, (BYTE*)sValue.GetBuffer(_MAX_PATH), &ulSize);
sValue.ReleaseBuffer();

C++

CString sValue;
ULONG ulSize = _MAX_PATH * sizeof(TCHAR);
lRet = RegQueryValueEx(hKey, NULL, NULL, NULL, (BYTE*)sValue.GetBuffer(_MAX_PATH), &ulSize);
sValue.ReleaseBuffer();

I guess that ulSize should be _MAX_PATH * sizeof(TCHAR); like in the second code ... but I am not sure ... can you tell me how is right ?

Thank you.

modified 8-Apr-15 5:37am.

Re: Buffer data size

Jochen Arndt8-Apr-15 1:58

Jochen Arndt

8-Apr-15 1:58

From MSDN RegQueryValueEx function[^]:

Quote:
lpcbData [in, out, optional]
A pointer to a variable that specifies the size of the buffer pointed to by the lpData parameter, in bytes.

So it must be the second version.

Re: Buffer data size

_Flaviu8-Apr-15 20:44

_Flaviu

8-Apr-15 20:44

Thank you !

Re: Buffer data size

Richard MacCutchan8-Apr-15 2:40

Richard MacCutchan

8-Apr-15 2:40

~~Version 1, as CString adjusts itself to the character type in use. See https://msdn.microsoft.com/en-us/library/aa314880%28v=vs.60%29.aspx[^]. A simple test wolud confirm it for you.~~

c graphics

vinay dahiya6-Apr-15 12:07

vinay dahiya

6-Apr-15 12:07

hey.....i have searched alot about c graphics and till now don't get any helpful information.
so i want to know some sites which can provide data about c graphics...basically i want to learn this....so do me a favor Confused | :confused:

Re: c graphics

Richard MacCutchan6-Apr-15 21:00

Richard MacCutchan

6-Apr-15 21:00

Do yourself a favour and study the documentation[^]. Google will find you some alternatives.

Re: c graphics

CPallini6-Apr-15 21:14

CPallini

6-Apr-15 21:14

The C programming language doesn't provide, by itself, functions for graphics. You have to use, in your application, the graphics API your system provides.

Re: c graphics

Stefan_Lang8-Apr-15 3:59

Stefan_Lang

8-Apr-15 3:59

As pointed out, C and C++ do not (yet) have built-in graphics capabilities. There are plenty of libraries for that purpose however, and plenty of articles offering advice on how to use them. What library to use strongly depends on the purpose you have in mind. I therfore suggest you feed the search engines of your choice with the keywords, "C", "Graphics programming" and maybe a keyword or two describing the application you have in mind.

I need to design a visual design tools for a private GUI library.

yu-jian6-Apr-15 6:38

yu-jian

6-Apr-15 6:38

Because it is difficult and wastes time for modifying the controls position in xml file directly.
Is anyone know how to design a good one as visual studio that cat drag and drop controls?

Re: I need to design a visual design tools for a private GUI library.

David Crow6-Apr-15 7:46

David Crow

6-Apr-15 7:46

yu-jian wrote:
Is anyone know how to design a good one as visual studio that cat drag and drop controls?

Yes, I'm sure someone out there has the ability.

"One man's wage rise is another man's price increase." - Harold Wilson

"Fireproof doesn't mean the fire will never come. It means when the fire comes that you will be able to withstand it." - Michael Simmons

"You can easily judge the character of a man by how he treats those who can do nothing for him." - James D. Miles

Re: I need to design a visual design tools for a private GUI library.

Sascha Lefèvre6-Apr-15 8:22

Sascha Lefèvre

6-Apr-15 8:22

I just happened to google that a few days ago:

http://support.microsoft.com/en-us/kb/813808[^]
http://stackoverflow.com/questions/5486009/custom-form-designer-by-using-visual-c-sharp-net[^]
Form Designer[^]

I have no experience with that but judging from what I've seen and read so far, it's far from trivial.

IoleUndoManager with Excel application

jaafar tribak6-Apr-15 5:45

jaafar tribak

6-Apr-15 5:45

Hi all,
First of all, I would like to apologize for posting this question in the C++ forum as it deals with Classic VB (VBA) ... The reason I posted here is because I can't get an answer (not even a hint) in the VB/VBA foums ... I searched the web extensively but without any luck

I hope you guys can ,at least, point me in the right direction

Problem:

I am trying to control the Undo/Redo Stack in excel but I can't seem to get a pointer to the UndoManager Interface in the ppv out argument when calling the QueryService Method .. it always returns Nothing ..

I hope someone can tell me what I am doing wrong .. I think the "SID_SApplicationObject" is not the right SID for what I am trying to achieve

Note : I am using the olelib.tlb

Code :

Sub Test()
    Dim pUnk As olelib.IUnknown
    Dim IServiceProvider As olelib.IServiceProvider
    Dim IID_IServiceProvider  As olelib.UUID
    Dim IID_IOleUndoManager As olelib.UUID
    Dim SID_SApplicationObject As olelib.UUID
    Dim ppv As IUnknown
    CLSIDFromString IIDSTR_IServiceProvider, IID_IServiceProvider
    CLSIDFromString "{0C539790-12E4-11CF-B661-00AA004CD6D8}", SID_SApplicationObject
    Set pUnk = Excel.Application
    pUnk.QueryInterface IID_IServiceProvider, IServiceProvider
    IServiceProvider.QueryService SID_SApplicationObject, IID_IOleUndoManager, ppv 
End Sub

Any help will be much appreciated
Regards.

Re: IoleUndoManager with Excel application

David Crow6-Apr-15 7:50

David Crow

6-Apr-15 7:50

jaafar tribak wrote:
First of all, I would like to apologize for posting this question in the C++ forum as it deals with Classic VB (VBA) ... The reason I posted here is because I can't get an answer (not even a hint) in the VB/VBA foums ... I searched the web extensively but without any luck

I do not see where you've asked this question in the VB forum.

Re: IoleUndoManager with Excel application

jaafar tribak6-Apr-15 13:14

jaafar tribak

6-Apr-15 13:14

Hi,

I did ask similar questions in the VB and COM forums before and in other websites as well .. but these rather difficult questions often remain ignored or without a propper solution .. I thought VC programmers were more confortable with these type of in depth subjects.

The very few vb lines in the above code snippet should be easy to understand by non vb programmers .. I hope that anyone fmiliar with ole/com would hopefully be able to give me (at least) a rough hint

Regards.

CFileDialog gives error "C:Windows\system32\config\systemprofile\desktop refers to location not available........

N3KK5-Apr-15 21:06

N3KK

5-Apr-15 21:06

I am starting my application by a Service. Now When I want to save a
file, I tried using CFileDialog. but when ever I select "desktop" it
prompts a message as "C:Windows\system32\config\systemprofile\desktop"
refers to location that iss unavailable. It could be hard drive on this
computer, or on a network... "

I checked that "C:Windows\system32\config\systemprofile" is available
but there is not desktop directory inside it.

Re: CFileDialog gives error "C:Windows\system32\config\systemprofile\desktop refers to location not available........

Richard MacCutchan5-Apr-15 21:56

Richard MacCutchan

5-Apr-15 21:56

You already asked this at CFileDialog gives error "C:Windows\system32\config\systemprofile\desktop refers to location not available........[^]. Please do not crosspost. If you have additional infortmation then edit your original question.

Re: CFileDialog gives error "C:Windows\system32\config\systemprofile\desktop refers to location not available........

N3KK5-Apr-15 22:16

N3KK

5-Apr-15 22:16

Sorry I didnt knw abt this

Re: CFileDialog gives error "C:Windows\system32\config\systemprofile\desktop refers to location not available........

Richard MacCutchan5-Apr-15 22:35

Richard MacCutchan

5-Apr-15 22:35

Then you should read the FAQ[^] or http://www.codeproject.com/Messages/2922875/HOW-TO-ASK-A-QUESTION.aspx[^] before posting.

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