C / C++ / MFC

Re: Register class, but I can't find memory leak of 1 byte, please help!

1-Feb-02 9:19

Your code has several bugs: (maybe one of them is causing the leak)

RegSetValue(HKEY_CURRENT_USER, _T(realPath), REG_SZ, _T(str), sizeof(realPath));

Here, sizeof(realPath) equals 4 (the size of a pointer) which is not what you want; use srtlen(realPath)instead.

TCHAR str[2048];
LONG strValue = sizeof(str);
RegQueryValue(HKEY_CURRENT_USER, _T(realPath), str, &strValue);
#pragma warning (disable : 4172)
return (LPCSTR)str;

Here you're returning a pointer to a char buffer constructed on the stack; this pointer becomes invalid as soon as the function exits (the buffer goes out of scope). I suggest you change the prototype of ReadString to return a CString and rewrite that portion of code like this:

TCHAR str[2048];
LONG strValue = sizeof(str);
RegQueryValue(HKEY_CURRENT_USER, _T(realPath), str, &strValue);
#pragma warning (disable : 4172)
return CString(str); // this takes care of allocating dynamic memory (which does not go out of scope)

Hope this helps.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

S van Leent1-Feb-02 10:43

S van Leent

1-Feb-02 10:43

Well, the problems are solved. I will upload the finished CRegisterEx when there are enough methods to be used.

LPCSTR Dutch = "Double Dutch Smile | :)

Learning STL

31-Jan-02 11:37

Can anyone recommend a good book for a c++ programmer wanting to learn STL?

Thanks

OMG | :OMG:

Re: Learning STL

Jon Sagara31-Jan-02 12:20

Jon Sagara

31-Jan-02 12:20

Christian Graus recommended the following:

"And you'll never regret it. Do you have any books ? I recommend STL tutorial
and Reference or Generic Programming and the STL ( probably the latter as it's a
better reference and moves faster ), and you will *need* Effective STL by Scott
Meyers, probably the best book I bought this year."

HTH

Jon Sagara

What about ?

Lost Macro/Add-in tab

David Chamberlain31-Jan-02 11:31

David Chamberlain

31-Jan-02 11:31

I'm getting back to development mode, and I find that the Tools/Customize window in VS6 no longer has a Macro/Add-in tab. Anyone have an idea what happened? The only tools that I know I was using were the Resource Organizer and the code-reformatter, both available on CP.

I loaded SP5 again, which was already installed, and re-booted, and still nothing.

Any words of wisdom (applicable to this problem) would be appreciated.

Dave

"You can say that again." -- Dept. of Redundancy Dept.

MSDN Jan 2002 with Visual Studio 6?

Ron Olson31-Jan-02 10:05

Ron Olson

31-Jan-02 10:05

Hey all-

For several years now, the standard M.O. for me has been that when a new version of MSDN was released, I would uninstall the previous version, then install the new version, and all would be ok from VS' standpoint.

I just installed MSDN for Jan2002 and have been greeted by a "MSDN not installed. Please install MSDN" error from within VisualStudio 6. I chose the same directory and such as I always have, but all of a sudden VS isn't finding it. Presumably it *should* work with 6, as I have found nothing in the documentation to say that it doesn't work, but perhaps I have to fiddle with the registry to have VS find it?

Thanks for any info,

Ron

Michael P Butler31-Jan-02 10:36

Michael P Butler

31-Jan-02 10:36

It is my understanding that from Jan 2002, MSDN will only intergrate with Visual Studio 7 and not version 6. If you want Version 6 integration you''ll need to keep October 2001 installed.

Michael Smile | :)

Michael Dunn31-Jan-02 11:34

Michael Dunn

31-Jan-02 11:34

Welcome to the f***ing world of .NET. You have to stick with the Oct 2001 MSDN in order to use it with VC 6.

"We're telling you where you will go today." -- Microsoft

--Mike--
"Everyone has figured out what 'service pack' really means, so they had to go and change the language. Perhaps this is what Bill was talking about in the 'security is top priority' letter."
-- Daniel Ferguson, 1/31/2002
My really out-of-date homepage
Sonork - 100.10414 AcidHelm
Big fan of Alyson Hannigan.

Not Active31-Jan-02 13:06

Not Active

31-Jan-02 13:06

I always run a seperate instance of MSDN rather than use it from VS.

Mazdak31-Jan-02 18:15

Mazdak

31-Jan-02 18:15

I installed new version of .Net last night,and MSDN was part of it,and many article is updated and changed.I think for VC++6 it is better to use old version of MSDN

Mazy

14-Feb-02 1:35

This is a post I put round work today re this:

"Dear All,

Be aware that the new MSDN Jan 2002 collection does not work with visual studio 6 (F1 for example produces an error).
A quick investigation reveals that MS have changed their help system (again) - it now uses the:

C:\Program Files\Common Files\Microsoft Shared\Help\dexplore.exe

'Document Explorer' to launch the collection. Since this is significantly different from .chm files and suchlike it ain't
gonna work for VS6. Their may be a way to hack around this - the collection is nominally launched through VS
via an intermediary DLL (vshelpui.dll - i think) and checks the following key

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\HTML Help Collections

Of interest is this -

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\HTML Help Collections\Developer Collections\0x0409\0x039a1a660

which points at the chm collection for old MSDN installs and tells VC6 where to find it.. Basically MSDN *used* to tell
VS6 where to find it and how to launch it. MS couldn't make MSDN compatible with VS6 and/or couldn't be
bothered to produce a patch for VS6 to launch things correctly.

You can add a tool to the tools menu (really) that launches the new MSDN via the following path

"C:\Program Files\Common Files\Microsoft Shared\Help\dexplore.exe" "

And yes, it sucks
Dead | X|

Simple question about DLL loading

14-Feb-02 5:22

Ok, me again. Worked out the following. You can install BOTH MSDN Oct
and MSDN Jan 2k2 on the same machine - and they work with both VS .NET and VS 6. Yay! We're using a network install here so the total cost of having
VS .NET plus two MSDN 'lite' installs is about 1 GIG.

Works for me..

Timbo
OMG | :OMG:

addObject()

31-Jan-02 10:04

i want to define my own add method that adds one object to some array every time it is called
does any one know how to do this please?
thanx

Re: addObject()

Not Active31-Jan-02 10:59

Not Active

31-Jan-02 10:59

Just do it.

<br />
bool CMyClass::AddObject()<br />
{<br />
  // Add object to whatever<br />
  MyArray[x] = new Object();<br />
<br />
  return I_read_book ? false : false;<br />
}<br />

RK_200031-Jan-02 9:58

RK_2000

31-Jan-02 9:58

Hi there,

I have a dialog wizard which I would like to perform its data integrity checks and its eventual task of inserting tonnes of data into various tables.

However, I need all the validations and eventual data insertions to be wrapped in a dll so other applications could use it as well.

How do I load this DLL into my exe wizard in Visual C++ and start using its member functions? what are the options and what is the best way of doing it?

thanks

Re: Simple question about DLL loading

Not Active31-Jan-02 11:04

Not Active

31-Jan-02 11:04

From a simple DLL standpoint you would use LoadLibrary("DllName") and GetProcAddress(...) to get access to the functions and use them.

I would however consider writing your data access component as COM. More portable and easier to use.

Help! About structure alignment

lucy31-Jan-02 9:23

lucy

31-Jan-02 9:23

I have a 4-byte data, it's content is:
bits 31-24 : pixel_data
bits 21-23 : unused
bit 20 : direction
bits 19-10: y_address
bits 9-0: x_address

So I construct a structure for it as follows:
#pragma pack(1)
typedef struct
{
unsigned int pixel_data : 8;
unsigned int unused : 3; /* must always be zero */
unsigned int direction : 1;
unsigned int pixel_x_address : 10; /* column */
unsigned int pixel_y_address : 10; /* row */
} FIFO_DATA_R_T;

it turns out the the pixel_data is at address bits 31-24, but unused is at bits 16-18.

How should I construct the struct? Confused | :confused:

many many thanx!

Re: Help! About structure alignment

Joaquín M López Muñoz31-Jan-02 9:58

Re: Help! About structure alignment

31-Jan-02 9:58

Hi Lucy. MS compiler has the following specific feature: bit fields are laid out from the least significant bit to the most significant bit. So your struct should be like:

#pragma pack(1)
typedef struct
{
unsigned int pixel_y_address : 10; /* bits  0- 9 */
unsigned int pixel_x_address : 10; /* bits 10-19 */
unsigned int direction : 1;        /* bit  20    */
unsigned int unused : 3;           /* bits 21-23 */
unsigned int pixel_data : 8;       /* bits 24-31 */
}FIFO_DATA_R_T;

This ordering is a compiler specific thing (Kernighan&Ritchie leaves it undefined, if my memory doesn't fail me).

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

lucy31-Jan-02 10:24

lucy

31-Jan-02 10:24

got it! Thank you so much! Rose | [Rose]

I'm lost!

31-Jan-02 8:28

c:\program files\microsoft visual studio\vc98\include\iostream.h(50) : error C2144: syntax error : missing ';' before type 'long'
c:\program files\microsoft visual studio\vc98\include\iostream.h(50) : error C2501: 'initialValue' : missing storage-class or type specifiers
c:\program files\microsoft visual studio\vc98\include\iostream.h(50) : fatal error C1004: unexpected end of file found
Error executing cl.exe.

i don't know y it tells me that there is some error with iostream.h class\
can any one tell me how to fix this please!
Confused | :confused:

Joaquín M López Muñoz31-Jan-02 8:37

31-Jan-02 8:37

Most probably the problem has not to do with iostream.h file, but with the file #included before it! Try swapping #includes to see what happens.

PS: IMHO it's advisable to have #include<iostream> instead of #include<iostream.h>: iostream (without the .h) is the latest version of the iostream library according to the C++ standard.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

31-Jan-02 8:50

i tried but it is still not working
every time i click the error it takes me to the iostream class file
any ideas?
thanks
Cry | :((

Joaquín M López Muñoz31-Jan-02 8:55

31-Jan-02 8:55

any ideas?

Yes, post the code Smile | :)

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo