C / C++ / MFC Discussion Boards

Re: trying to access functions in a dll created in VB

ThatsAlok8-Sep-09 21:14

ThatsAlok

8-Sep-09 21:14

time to learn com Smile | :)

A Beginner tutorial for writing simple COM/ATL DLL[^]

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sql: insert into ... mixed with english and unicode fields

includeh108-Sep-09 8:01

includeh10

8-Sep-09 8:01

assume the table has 2 fields: fe and fu.
fe (field-english) is english text field.
fu (field-unicode) is unicode text field.

also assume X is an unicode character, whose value is 1212 (hex word).

now we insert english string ab into field fe, Xa (values are 1212 6100) into fu.

how do we writesql statement?
i.e.

sql="insert into mytable (fe,fu) values(\'ab\', \'\x12\x12\x61\x00\' )";

the \x00 terminates the sql statement string.

any idea or suggestion?

(I am testing mysql database now, CString with unicode setting is not really suitable for mysql in the case).

thanks

Unit testing framework cfix 1.5 released; adds support for EXE targets and kernel mode multithreading

J. Passing8-Sep-09 7:26

J. Passing

8-Sep-09 7:26

Hi,

a new version of cfix, which is an open source unit testing framework
for user and kernel mode C and C++, is now available for download. Among
several minor improvements and fixes, cfix 1.5 adds two important new
features: The ability to implement unit tests as part of (existing) EXE
projects and support for multithreaded kernel mode unit tests.

For more details on these features, please refer to this blog post:
http://jpassing.com/?p=492

Updated cfix binaries and source code are available here:
https://sourceforge.net/projects/cfix/files/cfix/

Tutorials can be found here:
http://www.cfix-testing.org/doc/TutorialUserVsCc.html (Usermode C++)
http://www.cfix-testing.org/doc/TutorialUserVs.html (Usermode C)
http://www.cfix-testing.org/doc/TutorialKernelWdk.html (Kernel C)

Last but not least, in case you are a Visual Studio user, do not miss
out on giving Visual Assert Beta 2 a try -- it is an AddIn for Visual
Studio that seamlessly integrates cfix with the Visual C++ IDE:
http://www.visualassert.com/

As always, all kind of feedback is welcome!

--Johannes

Publish an RTMP stream to FMS using Microrosft Visual C

mseureka8-Sep-09 6:47

mseureka

8-Sep-09 6:47

Hi all,

I am getting a continuous video and audio packet from some source (Flv video codec) (Mp3 audio codec) and we have to send it to flash media server(or red5) through RTMP protocol.

Basically, I want to publish live stream through RTMP protocol to flash media server(or red5), so that there is live playback on a Flash player.

I am looking for a Visual C code snippet to do this.

Any suggestions on where to start and how to get this accomplished?

Many Thanks!

Re: Publish an RTMP stream to FMS using Microrosft Visual C

farnhamj12-Sep-09 14:32

farnhamj

12-Sep-09 14:32

RTMP is a propritary protocol, and Red5 is written in Java, so good luck on that one.

If you want to scour Red5's code for RTMP stuff and translate it to Visual C, I'm sure you could figure it out, but you might as well use other tools like ManyCam (free) and Virtual Audio Cable (like $15, I think) and patch stuff through to Adobe's Flash Media Live Encoder (which is free).

Re: Publish an RTMP stream to FMS using Microrosft Visual C

Sumit_Ghosh16-Sep-09 8:34

Sumit_Ghosh

16-Sep-09 8:34

Hi,

Thanks for your answer, I have got a better solution, Iam using RTMPD code for my application , its in vc++ and fits to my requirements.

Re: Publish an RTMP stream to FMS using Microrosft Visual C

Jon68z16-Oct-09 8:36

Jon68z

16-Oct-09 8:36

Hi,

Would you mind sharing your find? Which RTMPD did you find, use?

Thanks in advance...

Re: Publish an RTMP stream to FMS using Microrosft Visual C

Gavriloaie Andrei7-Nov-09 2:21

Gavriloaie Andrei

7-Nov-09 2:21

The home of the project is: http://www.rtmpd.com

There is an application written especially for that inside that server Smile | :)

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fly just fine. However, this
is not necessarily a good
idea. It is hard to be sure
where they are going to land,
and it could be dangerous
sitting under them as they fly
overhead.

Re: Publish an RTMP stream to FMS using Microrosft Visual C

Jon68z7-Nov-09 16:15

Jon68z

7-Nov-09 16:15

Hi,

Thanks for the response. Did you take that implementation and convert it over for a client application by any chance? If so, would you care to share your implementation?

Re: Publish an RTMP stream to FMS using Microrosft Visual C

Gavriloaie Andrei7-Nov-09 16:30

Gavriloaie Andrei

7-Nov-09 16:30

Lol, that whole thing is mine Smile | :)

Basically is doing the following:

flash publisher --> rtmpd --> streaming_server(rtmpd, FMS, etc) --> flash layer 1,2,...,N

Now, flash publisher talks with rtmpd via RTMP protocol (the first arrow). flash publisher is the "provider". But this can be changed. It can totally replaced with a custom internal stream. The over all structure would become:

rtmpd(doing screen capture INTERNALLY for example) --> streaming_server(rtmpd, FMS, etc) --> flash layer 1,2,...,N

You need to dig into the code a little bit though...

The server is running on:

Windows
BSD (Mac OS X, FreeBSD, NetBSD, OpenBSD, etc)
Linux (many distros here...)
Someone reported that ported it to SunOS. Not sure about that....

As a server, I recommend to run it on FreeBSD for best performance.

Have fun Smile | :)

Re: Publish an RTMP stream to FMS using Microrosft Visual C

Jon68z7-Nov-09 16:50

Jon68z

7-Nov-09 16:50

Hi,

Hmmm... I will have to check it out. I have not looked at the code repository yet. Although I am some what familiar with the project (at least I know where I can find it Poke tongue | ;-P

).

I want to use this with an open source server that is compatible with FMIS, such as red5, crtmp, etc. etc.

Anyway thanks for the heads up.

Implicit conversion from char * to string: g++ vs VS

dplong8-Sep-09 6:40

dplong

8-Sep-09 6:40

g++ 4.1.2 on codepad.org generates this error for the last statement in main(), below, but Visual Studio 2005 compiles it without error. Which is correct according to the C++ standard, or is this behavior undefined and both are correct?

In function 'int main()':
Line 13: error: conversion from 'const char [8]' to non-scalar type 'N' requested
compilation terminated due to -Wfatal-errors.

#include <string>
using namespace std;

struct N {
	N(const string & t_) { }
};

int main()
{
	string s1 = string("bananas");
	string s2 = "bananas";
	N n1 = string("bananas");
	N n2 = "bananas";
}

Re: Implicit conversion from char * to string: g++ vs VS

Stuart Dootson8-Sep-09 10:24

Stuart Dootson

8-Sep-09 10:24

g++ is correct. That line requires two user-defined conversions (const char* -> string -> N) in order for the only possible match for operator= (the one implicitly defined by the compiler for N). As C++ will only consider function matches that require one user-defined conversion (section13.3.3.1.2 of the 1998 standard), that operator= can't be used.

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

VC++ MFC Strlen [modified]

GC1048-Sep-09 4:09

GC104

8-Sep-09 4:09

Hi,

I have been trying to maniupulate a wide character string into an ansi character(8bit) string followed with some general string length checks:

//h-file
CString TxString; //initialised with "12345"
char* pOutputString;
size_t CharCountXyz;
int CharCount2;
int CharCount3;
char BasicString[100];
int CharCount9;

//cpp-file
...
pOutputString = CW2A(TxString); //convert wide character string into ansi string using MFC/ATL macro
CharCount2 = sizeof(TxString);  //returns 0x00000004 - as expected
CharCount3 = sizeof(pOutputString); //returns 0x00000004 - as expected
CharCountXyz = strlen(pOutputString); //returns 0xbaadfood - not what I expect!!!

//however if the following lines are added, this previous line behaves and returns 0x00000005
sprintf(BasicString, "ABCDEF");
CharCount9 = strlen(BasicString);

I added the last two lines to test strlen in its basic form, sure enough it worked when used to test 'BasicString' but curiously, the test on 'pOutputString' also worked???

modified on Tuesday, September 8, 2009 10:50 AM

Re: VC++ MFC Strlen

David Crow8-Sep-09 4:39

David Crow

8-Sep-09 4:39

GC104 wrote:
sprintf(BasicString, "ABCDEF");

Since BasicString is a pointer, have you allocated memory for it?

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Re: VC++ MFC Strlen

GC1048-Sep-09 4:52

GC104

8-Sep-09 4:52

Hi, sorry, I made a typo, should be:

char BasicString[100];

mistake made due to VC++ machine not on internet.

Geoff

Re: VC++ MFC Strlen

Stuart Dootson8-Sep-09 4:51

Stuart Dootson

8-Sep-09 4:51

GC104 wrote:
pOutputString = CW2A(TxString);

That's a bad thing to do - CW2A creates a temporary object to manage the ASCII string used to hold the result of the wide to ASCII conversion. That temporary object is destructed at the end of the line above, causing pOutputString to point at deallocated memory.

GC104 wrote:
sprintf(BasicString, "ABCDEF");

That's bad as well - mainly because you don't assign a value to BasicString - where is the "12345" going to go?!?!??!

You need to learn about pointers and strings and memory management in C/C++...

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

Re: VC++ MFC Strlen

GC1048-Sep-09 4:59

GC104

8-Sep-09 4:59

Thanks for feedback, I see your point made about the CW2A and memory deallocation - would be nice if this was made clear in the MSDN documentation!

Eventually, the "12345" will be sent through the serial port using 'WriteFile'. I have been under the imporession that the characters /strings need to be in an ansi 8 bit format for the writing to serial port to work. Any suggestions for an alternative to CW2A macro?

Sprintf(BasicString, "ABCDDEF") : Bad because I haven't initialised it as soon as I declared it? or the fact that I'm using sprintf to load the string?

I also take your point about needing to learn about pointers. I am wading through numerous c++ books but there's nothing like creating a real application Smile | :)

Re: VC++ MFC Strlen

Stuart Dootson8-Sep-09 5:17

Stuart Dootson

8-Sep-09 5:17

Easy one first:

GC104 wrote:
Sprintf(BasicString, "ABCDDEF") : Bad because I haven't initialised it as soon as I declared it? or the fact that I'm using sprintf to load the string?

Bad because it wasn't char BasicString[100]; when I answered the question - it was (IIRC) char* BasicString Smile | :)

Also - sprintf is less than optimal for assigning a string to another string - strcpy is better, I guess.

GC104 wrote:
Any suggestions for an alternative to CW2A macro?

CW2A isn't a macro. It's a class. There are a few alternatives:

Make sure that pOutputString has storage associated with it and strcpy the CW2A into it:
```
char pOutputString[1024];
strcpy(pOutputString, CW2A(TxString));
```
Declare pOutputString to be of type CW2A and assign TXString to it. THat way the storage is associated with the lifetime of pOutputString, which is what you want:
```
CW2A pOutputString = TxString;
```
Declare pOutputString to be of some other ASCII string type and assign CW2A(TXString) to it. That way there is storage associated with the lifetime of pOutputString, which is what you want:
```
std::string pOutputString = CW2A(TxString);
```

I'd go for option 2, personally.

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

VC++ MFC class data member initialisation [modified]

GC1048-Sep-09 1:59

GC104

8-Sep-09 1:59

I am learning to use VS2005 creating a VC++ MFC project to unterface to serial ports. I am in the initial stages of getting to grips with creating a serial port class. I am finding a few problems along the way with vartiable / data member initialisation.

CGCSerial h-file

int CharCount;
int CharCount2;
int CharCountThree;
CString TxString;
size_t InputStringLength;
TCHAR * pStr;
char * pOutputString;

cpp-file(s)

CMyDrawView::OnToolWrite2SerialPort
//member function called by clicking on windows menu item
{
CGCSerial *pGcSp = new CGCSerial(_T("12345")); //create instance of CGCSerial class
pGcSp -> GCTx; //call transmit member function
delete pGcSp; //cleanup
}

CGCSerial::GCSerial(TxString)
{
//constructor
CharCount2 = 0
CharCountThree = 0;
}

CGCSerial::~GCSerial
{
//destructor
}

CGCSerial::GCTx
{
InputStringLength = wcslen(TxString); //measuring length of incoming string
CharCountThree = sizeof(InputStringLength); //load CharCount3 with something
TempString.Format(_T("executing function CGCSerial::GCTx"));
AfxMessageBox(TempString);

pStr = TxString.GetBuffer(256);
CharCount2 = sizeof(pStr);
TxString.ReleaseBuffer;

InputStringLength = wcslen(pStr); //measuring length of

CharCount2 = 0x2345; // ###
CharCountThree = 0x5678; //###

CharCount2 = sizeof(TxString);
CharCountThree = sizeof(pOutputString);

pOutputString = CW2A(TxString); //convert wide string to ANSI string
...
...

}

My problem is that I admit this code doesn't look the most useful and is due to getting to grips with VC++ functions. The lines marked with ### don't seem to get executed! If I use the debugger, the debugger stops at these lines but upon viewing these data member's they do not get loaded with 0x2345 & 0x5678 respectively??? Is this a compiler bug??

any help would be greatly appreciated Smile | :)

modified on Tuesday, September 8, 2009 8:21 AM

Re: VC++ MFC class data member initialisation

CPallini8-Sep-09 2:10

CPallini

8-Sep-09 2:10

GC104 wrote:
CharCount2 = 0x2345; // ###
CharCountThree = 0x5678; //###

CharCount2 = sizeof(TxString);
CharCountThree = sizeof(pOutputString);

Maybe the compiler optimizes that to:

CharCount2 = sizeof(TxString);
CharCountThree = sizeof(pOutputString);</blockquote>

BTW please use the code block to submit code snippets.
Smile | :)

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Re: VC++ MFC class data member initialisation

Code-o-mat8-Sep-09 3:50

Code-o-mat

8-Sep-09 3:50

Could it be that you are debugging a release build?

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> Sometimes you just have to hate coding to do it well. <

Re: VC++ MFC class data member initialisation

GC1048-Sep-09 4:00

GC104

8-Sep-09 4:00

Hi all,

Thanks for responses. It looks like CPallini nailed it - the compiler doing its job! I have since added more data members to capture the results of the various functions I used on the original code. However this time, the debugger runs through eacdh line and loads each variable with the value I was expected

many thanks

Geoff Smile | :)

which module creates a specific file?

Joseph Marzbani8-Sep-09 1:25

Joseph Marzbani

8-Sep-09 1:25

Hi every body!
Is there any way/tool to find out which module creates a specific file? E.g one can see a process named Process.exe and this process has loaded a few DLL. What I want to know is which of theses DLLs creates a given file (e.g. C:\file.ext)

Thank you masters!

Re: which module creates a specific file?

Garth J Lancaster8-Sep-09 1:52

Garth J Lancaster

8-Sep-09 1:52

unless you have the source code to the dll, I doubt it after the file has been created and closed. If the file is open, there are tools around that are the windows equivalent of the 'lsof' command - systinternals (now part of Microsoft) has a tool to display (iirc) open files vs the processes that have them open

'g'

[edit] I was wondering if the file properties (custom) would be useful, but surely that depends on a well behaved application filling them out in the first place[/edit]

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