Re: ODBC programming - need help - C / C++ / MFC Discussion Boards

Antti Keskinen13-Sep-04 3:42

13-Sep-04 3:42

The best way to do shareware is always supply the user with an executable that is not fully functional at all, such as, some features are disabled in the code already.

If you use a serial number or an evaluation period, you need to go to very great lengths in protecting the application from hacking or date changes. While this is continous struggle as serial number generators and BIOS date modifiers are released by underground groups, it will eventually always end up as a victory for the underground. A human cannot make so good a protection that another human couldn't break it.

So, use two builds. The first one is the evaluation version, and will pop up a "Not supported in evaluation" message box, and the other build is a sales version, which you will send to the customer after he/she has paid the price. Of course, this method doesn't prevent the customer from copying the full software to his/her friends, but neither does a serial number system.

The best way to protect a software for single-machine use is to generate a checksum from the processor and motherboard serial numbers and then register this into your company's database when the program is first ran. If this registration fails, the software will not run. An alternative is to use a serial number system that is sent to you for validation. If the validation is not done, the software won't run either. This naturally assumes a network connection, but how many PCs are not connected into a network of some kind these days ?

-Antti Keskinen

----------------------------------------------
The definition of impossible is strictly dependant
on what we think is possible.

Re: Creating shareware

Hoornet9313-Sep-04 5:02

Hoornet93

13-Sep-04 5:02

yes ok, but our company already supplies software (in question) and it is already based on serial number protection. What I wanna do is an automatic upgrade system based on serials. My app must check the server for new version and then update it. Our company makes bussines on annual fees. So fro example when a company does not pay 4 the nexgt year we just remove their encripted serial number from the server. They can still download it from out ftp but the program must not work.

Love is the law, love under will.

Re: Creating shareware

Alexander ^M.,13-Sep-04 4:07

Alexander ^M.,

13-Sep-04 4:07

Always avoid to build software with serial checks, it is easy for crackers to hack it!
If you want to code a shareware then I propose that you put some features of the software in #ifdef blocks and undefine them when compiling the shareware. So crackers won't be able to reenable the features.

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

Re: Creating shareware

Henry miller13-Sep-04 4:33

Henry miller

13-Sep-04 4:33

I have to disagree with the other two responses. True someone can crack a serial number easially, but your goal should not be to stop the crackers, you will either fail, or incure other costs that are more than the gain. Remember, the crackers wouldn't buy your product anyway, so it isn't a lost sale.

The goal is to keep the honest people honest. It is easy to justify using a product a little more than allowed because you are planning on registering, but never get around to it. These are the people who you want to gently remind to pay.

There never will be a scheme that cannot be cracked. If it is hard enough it becomes an interesting challange and you just get more attention. Hardware checks are annoying at best, they drive some legitimate customers to buy your product, and then get a version from the underground so they don't have to deal with the stupid stuff!

I recomend you read all the articles at:
http://www.dexterity.com/articles/
I found several of them interesting.

Re: Creating shareware

Antony M Kancidrowski13-Sep-04 4:33

Antony M Kancidrowski

13-Sep-04 4:33

Yes you could have serial number checks or restrictive limitation for the application. However, when a full version is released, it has the potential to be copied, hacked etc.

IMO it is not worth putting a lot of effort into protecting the software. At best a protection system that stops casual copying between friends is all I would go for. As already mensioned, whatever protection you add to software someone will be able to remove it.

If the software is good enough and cheap enough then a percentage of people will register it. If you go for volume and therefore consumer awareness even a small percentage registrants will bring in the money.

Additionally, an insentive to register could be to get another application free, lifetime updates for the application. That sort of thing.

Ant.

I'm hard, yet soft.
I'm coloured, yet clear.
I'm fruity and sweet.
I'm jelly, what am I? Muse on it further, I shall return! - David Williams (Little Britain)

ODBC programming - need help

acroitoriu13-Sep-04 2:47

acroitoriu

13-Sep-04 2:47

I just started programming VC++6 with database support and I already have a major problem: I created a SDI application and when I choose only one table from the Access database everything goes well. But I can't handle 2 or more table from the same database.... How do I use 2 or more table and how do I execute queries(SQL) on tables??? Confused | :confused:

I really need help as soon as possible...
A small application using a database with 2 or more table and which shows how to execute SQL queries on different tables would be great... I would really appreciate that!

Please help me... Blush | :O

Croitoriu Andrei
croi2001@yahoo.com

Re: ODBC programming - need help

Hardy_Smith13-Sep-04 2:52

Hardy_Smith

13-Sep-04 2:52

I would recommand you to use a real database server, Firebird for example.

www.ibphoenix.com

Do you want to program odbc lowlevel? If not, take a look at the database-Classes here in codeproject.

http://www.codeproject.com/database/#ODBC[^]
There are some examples.

Hardy.

Re: ODBC programming - need help

David Crow13-Sep-04 4:05

David Crow

13-Sep-04 4:05

The SQL query generated by ClassWizard should have formed the JOIN clause automatically. In case it didn't, you'll need to do it manually. For example, here is a JOIN on three tables of a database I recently worked on:

SELECT [Meet].[Name], [Meet].[Date], [Gymnast].[Name], [Scores].[Score1]
FROM Meet INNER JOIN (Gymnast INNER JOIN Scores ON [Gymnast].[AutoNumber]=[Scores].[GymnastNum]) ON [Meet].[AutoNumber]=[Scores].[MeetNum]
ORDER BY meet.date;

Search MSDN for different examples of LEFT, RIGHT, INNER, FULL, CROSS, and OUTER joins.

"When I was born I was so surprised that I didn't talk for a year and a half." - Gracie Allen

IS thre any COM Port Event ?

zahid_ash13-Sep-04 2:24

zahid_ash

13-Sep-04 2:24

HI ,

I want to write a program, which Continuesly read from COM port.

but i want to do , as data Come on COM port it reads it , and use accoedingly.
I not want to that it reads in Continuse loop . and remain busy .

i want as in Socket as data recives event fires then we recive it and use it.

is there any event that is fired when data
is come( written) on COM port.

thanx

Regards.

Re: IS thre any COM Port Event ?

Antti Keskinen13-Sep-04 2:34

Antti Keskinen

13-Sep-04 2:34

Yes and no. The COM ports, by default, are continous IO. They don't fire events unless you specify so, and tell them what events they fire. This is called asynchronous communication, or overlapped IO, and is fairly well covered by many articles in the Net.

Here[^] is a link to one, right here on Code Project.

-Antti Keskinen

----------------------------------------------
The definition of impossible is strictly dependant
on what we think is possible.

Linker warning: Multiple ".rdata" sections with different atrributes

kc200313-Sep-04 2:20

kc2003

13-Sep-04 2:20

I am working with VC++ 6.0 with Windows-DDK installed in the system and correct Directory-path (Include & Library) set. After compilation of any VC++ project from workspace when I start the build-process, I am getting a linker-warning as follows.

[LINK : warning LNK4078: multiple ".rdata" sections found with different attributes (C0000040)]

My project-setting involves "Incremental-Linking" and I am using Debug-build. This is not a project-specific warning. Any simple MFC application is throwing this LNK-warning during build.
If anyone has come across this situation, please let me know how to get rid of this problem... D'Oh! | :doh:

Koushik Chakrabarti

Re: Linker warning: Multiple ".rdata" sections with different atrributes

Alexander ^M.,13-Sep-04 4:09

Alexander ^M.,

13-Sep-04 4:09

if this warning doesn't cause any problems with the software then you can easily ignore it.

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

istream: seekg / tellg, peculiar behaviour

LiquidEyes13-Sep-04 1:39

LiquidEyes

13-Sep-04 1:39

I'm having two istream-related problems. Please can somebody help... Confused | :confused:

Problem 1

void loadStuffFromStream (istream& stream)
{
	// goes too far!!
	stream.seekg( length, ios_base::cur );
}

***edited*** This seems to skip to an arbitrary position in the stream, instead of 'current position' + length bytes. Why does it do this?

Problem 2

char ch;
int pos;
...
pos = stream.tellg();		// now pos=0
stream.get (ch);
pos = stream.tellg();		// now pos=3585 ???
stream.get (ch);
pos = stream.tellg();		// now pos=3586
stream.get (ch);
pos = stream.tellg();		// now pos=3587
stream.get (ch);
// etc...

Not so much a 'problem' as a matter of curiosity. Why is there a sudden leap in the read-position reported by tellg the first time I read from the stream? (N.B. It is reading the correct characters into ch!)

about transmiting video through net

yingkou13-Sep-04 0:44

yingkou

13-Sep-04 0:44

I want to know something about video chat.for example:whici protocal is preferred,which Interface is used to record video data and audio data.
I also want to know whether the data structure used to store the video data and audio data is the same.if not,the procedure of recording video and audio is separately executed.IGraphicBuilder and ICaptureGraphBuilder2 are used to capture video. and Recording audio data is execute by another interfaces?

please help me,thanks a lot

Re: about transmiting video through net

Alexander ^M.,13-Sep-04 5:03

Alexander ^M.,

13-Sep-04 5:03

you question is very very general. what about fetching some information before asking?
there are articles about video capturing on cp!

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

Re: about transmiting video through net

yingkou13-Sep-04 15:33

yingkou

13-Sep-04 15:33

Could you give me some advices? such as book,URL etc. Thanks a lot

Re: about transmiting video through net

Un13-Oct-04 4:14

Un1

3-Oct-04 4:14

get the code here:

http://www.planet-source-code.com/vb/scripts/BrowseCategoryOrSearchResults.asp?optSort=Alphabetical&txtCriteria=video&blnWorldDropDownUsed=TRUE&txtMaxNumberOfEntriesPerPage=10&blnResetAllVariables=TRUE&lngWId=1[^]

Console in C++?

Hadi Fakhreddine13-Sep-04 0:43

Hadi Fakhreddine

13-Sep-04 0:43

Hi,
how can i use the Console in vc++ .net?
I've seen an example code at MSDN like:
Console::WriteLine("blabla");
However, I need to reference the "System" namespace i guess...It's easy to do that in VB.NET and C# but how to do that in VC++.NET ?
Thanks

Re: Console in C++?

Antti Keskinen13-Sep-04 2:43

Antti Keskinen

13-Sep-04 2:43

There's one crucial difference.

VC++ .NET is standard C++, you can write console applications by creating a file that contains the function main and links with the C Runtime Library.

However, Managed Extensions for C++ (MC++) is the C++ version you use to write software for .NET Framework. MC++ is the language that can be compared with C# or VB .NET, for example. VC++ .NET is not a .NET language.

In MC++, you need to use the import statements to use the .NET Framework. For example:

#import <mscorlib.dll> // Required for all .NET applications
#import <system.dll> // the System namespace<DIV>

// Call the console
System::Console::Writeline( L"BlaBla" );

Microsoft is currently developing the C++/CLI specification, which is MUCH more flexible and usable than MC++. To write programs with this language, you need to have the Visual C++ Express 8 Beta version, available from Microsoft as a free download.

-Antti Keskinen

----------------------------------------------
The definition of impossible is strictly dependant
on what we think is possible.

Re: Console in C++?

Hadi Fakhreddine13-Sep-04 4:44

Hadi Fakhreddine

13-Sep-04 4:44

Thanks a lot Smile | :)