Re: Best alternative to GDI/GDI+ for simple 2D games - C / C++ / MFC Discussion Boards

Re: Counting items in a file with a C++ program

«_Superman_»24-Jul-09 17:37

24-Jul-09 17:37

You could create an object of std::map<int, int=""> where the first int (key) is a number in the file and the second int (value) is the count.

After extracting each number from the file, check if it exists in the map.
If the number is found, increment its value, otherwise create a new entry.

Then you can iterate the map to get the count of each number.

«_Superman_»
I love work. It gives me something to do between weekends.

C++ library to send mail via SMTP in HP UNIX

ray_matt24-Jul-09 9:52

ray_matt

24-Jul-09 9:52

Hello Gurus,
I am a java guy. I am sorry if my below post sounds basic stuffs. Basically I am working for a project that has C++ back-end and Java in the front-end.

Currently developing a module that sends out an e-mail message (just plain text) to all recipients and/or group of recipients from Java GUI that uses C++ back end running on HP-UNIX to send mail using "sendmail" command via SMTP. After having spent quite a bit of time trying to figure out a way to get the delivery status back off of SMTP server (to display the status for each recipients in GUI), I have been unable to find a way to get this job done. I just piping the message (C++ code) to server that contains "sendmail" command along with address and message body.

I was hoping to find out - Is there a library api available for C++ to send mail via SMTP to make life easier? Or is there a simple C++ code that does this, basically I would have to get the delivery status for each recipients.

I am looking for something similar to CSMTPConnection v1.36[^] that I can use for HP-UNIX (I guess this was developed for Windows MFC) OR can I still use the same for C++ running on HP-UNIX as well ?

I would truly appreciate any input/suggestion on this.

Many thanks!

-RD

Re: C++ library to send mail via SMTP in HP UNIX

Rozis24-Jul-09 13:19

Rozis

24-Jul-09 13:19

If you understand the concept of sockets if could send you some code the can be ported to C++...

But i was wondering: I guess there's a SMTP-class in Java - why not use that one?

Rozis

Re: C++ library to send mail via SMTP in HP UNIX

ray_matt25-Jul-09 6:09

ray_matt

25-Jul-09 6:09

Thanks!

As I said earlier - I am doing some enhancements to existing application that is built on C++ back end. So C++ not only sends mail out but also does other stuffs. I know that I can use Java to do this but I got to use C++ (Real Time server that runs on HPUX).

All am looking for is a way to read the response back from server that tells whether or not message is delivered.

Any help would be greatly appreciated!

Thanks,
RD

Re: C++ library to send mail via SMTP in HP UNIX [modified]

ray_matt27-Jul-09 6:02

ray_matt

27-Jul-09 6:02

just pumping it up guys - tried to google it - do find couple of library that does this for you but problem is that either got to pay for it or library with whole bunch of other stuffs that you got deal with. Could not help.

really looking for something simple ..c++ library api OR c++ code which is simple enough to send mail using sendmail command & tells the delivery status for each recipients.

I really appreciate any inputs or suggestions...

-RD

modified on Monday, July 27, 2009 5:09 PM

How to enable "Prev Page" button in Print Preview dialog using MFC?

gshen24-Jul-09 9:30

gshen

24-Jul-09 9:30

I created an MFC application and added Printing and Print Preview capability to a CMyFormView derived from CFormView. The problem is that the "Prev Page" and "Zoom Out" buttons on the Print Preview toolbar are always disabled whether the second, third or last page is displayed. The "Next Page" button are always enabled and work correctly.

For the Prev Page button, I set CPrintInfo::SetMaxPage() and CPrintInfo::SetMinPage(). However, this doesnt work to enable the Prev Page button. In debug mode, I could see that CPrintInfo::m_nCurPage value was correct within OnPrint() method when the program is in print preview. Anybody knows how to enable Prev Page button in Print Preview dialog?

Thanks

Sheng

Best alternative to GDI/GDI+ for simple 2D games

Adassus24-Jul-09 9:16

Adassus

24-Jul-09 9:16

Hi all,

I'm trying to find an alternative to GDI and GDI+ for simple 2D games since it doesn't look like GDI/GDI+ are made for that (having flicker issues with GDI+).

I plan on using bitmaps and animating them. I heard of SDL and Allegro. Anything else out there I'm missing? In your experience, which do you prefer?

My language of choice is C++.

Re: Best alternative to GDI/GDI+ for simple 2D games

Randor 24-Jul-09 9:27

Randor

24-Jul-09 9:27

Adassus wrote:
Anything else out there I'm missing?

Whats wrong with DirectX[^]?

Best Wishes,
-David Delaune

Re: Best alternative to GDI/GDI+ for simple 2D games

Moak25-Jul-09 3:34

Moak

25-Jul-09 3:34

Adassus wrote:
having flicker issues with GDI+

Perhaps use two buffers one to show and one to draw and then swap them:
- with GDI use CMemDC[^]
- with OpenGL use SwapBuffers[^]
- for an alternative GUI framework see QT[^]

/M

My webchat in Europe Java | [Coffee]

How to calculate checksum

resolvequestion24-Jul-09 9:05

resolvequestion

24-Jul-09 9:05

I came across so many checksum calculation but I need to implement the checksum as below

I have packet coming in of 60Words , 2W and 256W and for all this I need to verify checksum with checksum present in the header of each packet... the algorithm that has been recommended as below.....

Mod 128 sum of all the 4-bit nibbles in the packet. Checksum field set to zero prior to calculating .... I dont understand thi can someone help me out

THANKS!!!!

Re: How to calculate checksum

Emilio Garavaglia24-Jul-09 9:27

Emilio Garavaglia

24-Jul-09 9:27

Just study what the & | ~ << and >> operators ar for.
We don't do class assignmetns.

2 bugs found.
> recompile ...
65534 bugs found.
D'Oh! | :doh:

Re: How to calculate checksum

«_Superman_»24-Jul-09 17:47

«_Superman_»

24-Jul-09 17:47

Extract 4 bits from each byte using bitwise operations.
Look at this Bitwise operation[^] link on how it can be done.

Divide this number by 128 and take its remainder.
You can use the % operator for this.

Add all the remainders together to get the checksum.

«_Superman_»
I love work. It gives me something to do between weekends.

Support asked for virtualising a program in Vista using TokenVirtualizationEnabled using SetTokenInformation

Kees195824-Jul-09 8:57

Kees1958

24-Jul-09 8:57

Dear all,

In Vista one can manually set a process virtualised using the taskmanager and right clicking the process, next setting it virtualised.

I need a little program starter (for ease of use lets call this startvirtualised.exe) which can be passed a location of a program (e.g. C:\Program Files\Example.exe).

The code I woul dlike to have should

a) Start the process "C:\Program Files\Example.exe
b) Set the TokenVirtualizationEnabled
c) Exits

Thanks in advance, I would pay for the time it would need to code this

DSA algorithm

sarroya24-Jul-09 7:38

sarroya

24-Jul-09 7:38

Hi,
i'm working now to complete DSA algoritm but i can't...
help me to complete thes algorithm
i'm work in c++ and i came copy to header files like sha1.h /
cdefs.h /null.h /wchar.h
featuretest.h / cdefs_aout.h /cdefs_elf.h/ common.h/ ast_common.h/
int_type.h/ ansi.h
i put all this in INCLUDE file and SYS
but featuretest.h can't open
please tell me what i can do ??????? Cry | :((

How to store array in vector in C++

resolvequestion24-Jul-09 7:30

resolvequestion

24-Jul-09 7:30

I am using vector to store the incoming data. Now my data is stored in Struct. I want to store only "bydata[]" from my structure into vector.... as the data keeps coming in.... I will just keep adding at the end of the vector "bydata[]" .....
How do I store this data using vector... or theres any other method tht I can use it.....

#define MAX_DATA_BYTES 60
typedef struct
{
unsigned char CheckFlags;
unsigned char Checksum;
unsigned short SequenceCounter;
} sHeader; //

typedef struct
{
sHeader Header;
unsigned char byData[MAX_DATA_BYTES];
} sData; //

Below code shown previously stores the entire structure... but I just want the "sData.byData[]" to be stored....

Please can someone help me.....

modified on Friday, July 24, 2009 3:01 PM

Re: How to pass array inside Vector in C++

transoft24-Jul-09 7:57

transoft

24-Jul-09 7:57

typedef vector<Whatever> WhateverV;

int Store(Whatever const& w, WhateverV vw)
{
vw.push_back(w);
}

Re: How to store array in vector in C++

«_Superman_»24-Jul-09 17:59

«_Superman_»

24-Jul-09 17:59

Create a vector of unsigned chars - std::vector<unsigned char> vBytes;
To copy the received byte to the end of the vector do this - vBytes.insert(vBytes.end(), size);

If you want to implement some sort of queue where you also consume the data you should use the deque class instead of vector.

«_Superman_»
I love work. It gives me something to do between weekends.

Tab control implementation in MFC document / view application. [modified]

Vaclav_24-Jul-09 5:55

Vaclav_

24-Jul-09 5:55

Which is more appropriate to use in MFC document / view architecture to display (view) the document - CTabCtrl or CCtrlView?
I am looking at the CTabCtrl as a control “overlay” of views. Is that correct? For lack of other words – the document communicates with tab class first and the tab class than communicates with tabs / plain views.
Or would using CCtrlView be simpler?
Any constructive comments as always are appreciated.
Cheers Vaclav

PS I forgot to mention "minor" detail - currently I am using CCtrlView with CTabCtrl variable with some isssues.I need to investigate if CTabCtrl can be used directly as a view anyway.

modified on Friday, July 24, 2009 12:07 PM

safely returning classes from functions... when and when not to construct !

paolosh24-Jul-09 5:04

paolosh

24-Jul-09 5:04

Hi all,

Am i right in thinking that foo() is a very SAFE and SLOW way of passing stuff around, whereas bar() which is LESS SAFE but FASTER.

MyClass foo()
{
MyClass x;

// do something with x

return MyClass(x);
}

MyClass* bar()
{
MyClass * x = new MyClass();

// do something with *x

return x;
}

If i call foo() with something like MyClass c = foo(), there will be:-

1 instantiation, 2 copies, and 1 destruction + overhead of "do something with x"

If i call bar() with something like MyClass *b = bar(); delete b, there will be:-

1 construction, 1 destruction + overhead of "do something with x"

So, for internal codey type functions which are protected from the user, it would be quite acceptable to use a bar() type mechanism in order to gain more speed.

However, for functions designed to be used by an external user in a safe way, we should stick to foo().

Paul

Re: safely returning classes from functions... when and when not to construct !

josda100024-Jul-09 8:21

josda1000

24-Jul-09 8:21

I believe that both will have the same amount of time. You have no reason to, at the end of foo(), 'return MyClass(x);', because this will cast a MyClass object to MyClass (redundant), which in effect calls the copy constructor for MyClass. Basically, whether you use the stack or the heap, this function would have done the same exact thing if you did not call that copy constructor. And, as long as you delete the object in bar(), it is totally safe, in my opinion. If my thoughts seem incorrect, I'd love to hear about it... I could be wrong of course.

Re: safely returning classes from functions... when and when not to construct !

paolosh24-Jul-09 23:48

paolosh

24-Jul-09 23:48

No, you are correct !

After playing around with the code and debugging I found what you said to be true. I am learning on the job, so sorry for the confusion in my original code.

Thanks for your help,

Paul

Beginner: How to access elements in a Variant array of Variants (8204)

BeerFizz24-Jul-09 4:19

BeerFizz

24-Jul-09 4:19

Hi,

I have an array of variants, but I'm unsure how to access the individual elements withing this array:

_RecordsetPtr ptrRS;

ptrRS = wr->GetData();	// returns a record set of rows from a table
		
_variant_t vtRows = ptrRS->GetRows(adGetRowsRest);

int vt = vtRows.vt;

str3.Format("vt %d", vt);
MessageBox(str3);		//  displays 8204
			
_variant_t vRow;
vRow = vtRows[0];		// does not compile

Could someone please assist me with a code snippet on how to do this.

Thanks
Phil

Returning large objects from a function without unnecessarily invoking the constructor !

paolosh24-Jul-09 3:31

paolosh

24-Jul-09 3:31

Hi all, hope you could maybe give me some advice on the following...

Is the following code legal?

MyClass foo()
{
MyClass * p = new MyClass();

// do something to *p here

return *p;
}

void test()
{
foo();
}

void main()
{
test();
}

The above code compiles and works fine. The intention is to create a MyClass instance in foo, and return it without onvoking the constructor on exit. I then want this instance to be available in test. On exit of test i want this instance to be automatically deleted.

It seems to work fine, but when I use the same mechanism in large programs, including classes etc., I am running into some difficulties when the "return *p" executes.

Thanks,
Paul
Wink | ;)

Re: Returning large objects from a function without unnecessarily invoking the constructor !

transoft24-Jul-09 3:43

transoft

24-Jul-09 3:43

In your

void test()
{
foo();
}

You did not handle "p". This is a memory leak. You should delete p;

void test()
{
  Myclass* p = foo();

do something with "p" then

  delete p;
}

Re: Returning large objects from a function without unnecessarily invoking the constructor !

paolosh24-Jul-09 3:51

paolosh

24-Jul-09 3:51

Thanks for the reply.

I've debugged the presented code step by step and witnessed that the compiler deletes p itself on exit from test() !

However, the presented code is not OOP. When the same mechanism is used in an OOP set-up SOMETIMES I get errors. Perhaps I'm missing something.

--------------------------------------------------------------

Anyway, is there a way to achieve what I want without having to delete p by hand?... I basically want to instantiate an object in foo and then return it to the calling function. I would then like the calling function to auto-delete that instance on exit.

Paul

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