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You should get a C book and Read. And if you have specific problems, please post them here.
"If A is a success in life, then A=x+y+z. (Work is x; y is play; and z is keeping your mouth shut.)"
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Hello all,
In my Header file:
class MyData
{
struct Fparams
{
int i;
bool flag;
};
}
Now in CPP file:
void MyData::GetData()
{
Fparams fParam;
fparam = AllData();
}
MyData::Fparams MyData::AllData()
{
Fparams fparam;
fparam.i = 5;
fparam.flag = true;
return fparam;
}
Now i get an error saying - error: no match for 'operator=' in fparam = AllData(); ........
What's wrong here? How can i fix this?
Thanks in advance.
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Make your nested structure public and declare the member functions in your class first then see what happens.
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Well one problem is that in the AllData() function, you're returning a struct that is declared inside the function itself.
This is no good because when the function exits, all the variables declared inside the function are destroyed, so you're returning something that no longer exists.
It would be better if you wrote it as:
void MyData::GetData()
{
Fparams fParam;
AllData(fParam);
}
Void MyData::AllData(Fparams& params)
{
params.i = 5;
params.flag = true;
}
The difficult we do right away...
...the impossible takes slightly longer.
modified 24-Oct-13 16:00pm.
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You can return objects that are declared local to a function from a function. That's what copy constructors are for...
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Thanks a lot everyone, it's solved
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You need to override the = opperator for the struct so that all the data is copied back.
Or use a pointer and pass it to the func, which is better, and a lot lighter on the stack.
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Looking at the error there's probably a missing equality operator, but why's not obvious as we haven't got the full class definition.
And it's not better to pass a pointer rather than returning a value - a decent compiler C++98 compiler will implement NRVO which makes it just as efficient to return a value.
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And the code ends up different to what you intend...
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Hello community
I´m really interested in these subject, but i dont really how works implementation off ecc in hardware, did you ever did that for a hardware ecc with c++? ,could you show me maybe an example of a ecc implanted in hardware with c++?
Because im looking for a security for my hardware and i want to try ecc with c++ for my hardware ( µBIC).
Maybe anyone have a example code for a hardware with ecc in c++.
thx
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Hi all,
I'm a newbie in Linux programming. I compile the "Hello world program" by means of gcc compiler in a Centos 6 host computer, with kernel 2.6.32. The command line used is gcc -static hello.c -ohello. Previously I have installed the GNUlibc (ver 2.12) in this computer.
The compile process is ok, and runs ok in the host computer (Pentium 4). When I copy the program to an embedded cpu with AMD GEODE LX800 processor and kernel 2.6.12, the running result is "error: illegal instruction"
I checked compile with different parameters in gcc command line: -mpc64, -m32, -march=i386, -march=geode with no results with any of them (compile is ok but running error "illegal instrucion")
I know a cross compiling is neccesary but don´t know the correct parameters to gcc to use
The code is as simple as this
main()
{
printf("Hello world\n");
}
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i'm a new learner for C++
i want to use a easy software to practice
i need some advice...
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Visual stadio will be ok 4 y
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thx, i will try this software!
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As an IDE, Visual C++ without doubt.
Plus I regularly use Notepad++ (use instead of notepad). Lightweight and cool.
"If A is a success in life, then A=x+y+z. (Work is x; y is play; and z is keeping your mouth shut.)"
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my teacher advised us to use VC++
Notepad++ sounds cool!!
thanks for your advice!
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Any time.
Best Regards !
"If A is a success in life, then A=x+y+z. (Work is x; y is play; and z is keeping your mouth shut.)"
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Stay away from both codeblocks and NotePad++. Visual C++ Express provides everything you need, and it or its professional cousins, are the IDE of choice for most people who answer questions here.
Veni, vidi, abiit domum
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It depends on what your host operating system is.
If you're running Windows then I'd suggest either Microsoft Visual C++ Express or MingGW and a text editor of your choice. From recent experience of teaching a couple of newbies Visual C++ was a bit of a cognitive load at the same time as learning C++ - you have to deal with some non-C++ bits that you have no idea about at first. MinGW is a bit simpler to get started with - the cognitive load is still there but spread slightly differently.
If you're running on Linux or something like FreeBSD then install g++ and use that.
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notepad and a GNU compiler. Come on, do it the MANLY way! 
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At the very beginning I would recommend you to go with notepad + gcc. This would be very useful in order to understand the compilation model (how c/cpp/h files work) and linking. This is very useful/necessary knowledge that you need even when you are using an IDE with a larger project to help you in development. If you later switch to an IDE then on windows Visual Studio is by far the best. If you are using a better version than the free Visual Studio Express edition then you can use plugins/addons like VisualAssistX and Productivity PowerTools to make it even better. On MacOSX you can use Xcode. On linux code::blocks, this is a free ide that is crossplatform, available on all other platforms.
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