I want to make the transition from programming in Microsoft Visual to programming in KDevelop. I thought it would be pretty straitforward, C++ is C++ after all. I did learn the "Using namespace std" thing, but I still cant compile any of my programs that worked fine in MSVisual, after adding "using namespace std"
Is it just the compiler or for some reason is the code different in Linux? If its the latter, I need to find a documentation on programming for linux. Preferably one for complete beginners, starting of with "hello world" Either that or im just going to go back to MSVisual. Any help would be appreciated, maybe someone has gone through the same thing?

What errors do you get when compiling?
Searching google/linux for info on that. You will surely find someone who had the same problem and will show you what are the diferences.

If you're used to programming in Visual C++, you're probably used to some of the Windows API (the functions used for creating windows, dialog boxes, drawing stuff on the screen, etc.), which is not going to work in Linux. Yes, C++ is C++, but keep in mind that C++ is simply a language. Function names are like words, and Linux has a different vocabulary than Windows.

There are lots of programming resources online. Google will give you tons. Also, you can get the source code for just about anything in Linux, meaning you can always study that and learn from it!

g++ supports the Standard C++ STL while MSVC++6 has scant support of the STL and uses it's own classes for example it uses some class called Cstring instead of the STL string class. Microsoft fixed that in VC++7, but it is not reflected in MFC unfortunately, yet not even Linux widget sets support Standard C++. So the GUI libraries are just totally different on both platforms (since there is no standard support on either!).

If you wanted a cross platform solution, than you would have to use Java < http://members.shaw.ca/trollking/ >.

Although I admit, that I don't know what the newest QT versions are like, nor the newest GTK+. Maybe they are more ANSI compiant.

C++ is C++ but dfferent platforms added their own libraries to add the functionalities. The core language and standard libraries are more or less the same, and you shoud be able to compile the programs using only the standard libraries with no or little changes. But each platform adds their own libraries. You might want to search "Linux C++ programming" in the google and you will get tons of tutorials.

Not really unfortunately. For example Microsoft VC++6 does not support the STL very well at all. So I'd have to totally 100% disagree that MSVC++ is Standard C++, or that toolkits like QT or MFC conform to ANSI.

The only fortunate thing is that g++ and the new MSVC++7 are ANSI compliant, however their toolkits and API's are not ANSI compliant, and that is not good.

If you don't believe me than try titles from the Bjarne Stroustrup series (the creator of C++) or a book like C++ Primer 3rd edition on MSVC++6. Than you'll know what a piece of junk MSVC++6 is! Than read about the Linux toolkits that state they are not compliant with Standard C++, they have a ways to go. The fact is that Standard C++ is the most sophisticated langauge around, and I'd like to use it with a widget set on Linux, but that isn't possible yet, or at least not without creating your own Widget set from Xlib.

Ouch. I've been programming in MSVisual C++ 6, looks pretty bad. But I get syntax errors on the simplest programs. For example:
#include <iostream>

int main ()
using namespcae std;

{
long games, computer, total;
do {
cout << "how many times do you play video games a week?: ";
cin >> games;
cout << "how many times do you use the computer a week?: ";
cin >> computer;
total = games + computer;
cout << total;
cout << "If you want to go again, type 1 for yes and 0 for no.";
} while (again !=0 );
return 0;
this little one produves errors like games and computers are undeclared, and that there are syntax errors before >> and <<<
This worked toatally fine in MSVisuall C++, but I gues it just sucks.

I have heard several reports that Visual C++ is not an ANSI compliant compiler, which means it will probably accept syntax that is really not valid. Instead of just saying "long" try "long int" or "long unsigned int", etc.

Another thing I have been told about one of Visual C++'s quirks, is in the following situation:

for ( int i = 0; i < 10; i++ )
... some stuff

for ( int i = 0; i < 10; i++ )
.. some other stuff

This is legitimate, ANSI-compilant C++. The variable i should be in scope only for the duration of the for loop, which saves the hassle of declaring it outside the for loop. But Visual C++ keeps it in scope, so the second for loop causes errors about multiple declaration. Fun, eh? Guess the MS guys didn't work too hard on compliance.

I made a little bit changes to your program.
The problem is you miss placed the "using namespace std".
Try to copy and compile the following program.
It's working fine.


#include <iostream>

int main ()
{
using namespace std;
long games, computer, total;
int again;

do {
cout << "how many times do you play video games a week?: ";
cin >> games;
cout << "how many times do you use the computer a week?: ";
cin >> computer;
total = games + computer;
cout << total;
cout << "If you want to go again, type 1 for yes and 0 for no."; cin >> again;
} while (again !=0 );
return 0;
}

I've always seen the 'using namespace std' outside of any function definitions. I don't think it belongs inside of main, since it's really a compiler directive, rather than part of the main function.

Though, I just noticed that Fingel has 'namespace' misspelled. Fingel, if you copy-pasted this program, you might want to see if correcting the spelling helps

Yeah! actually should be outside of the function definitions, like,

#include <iostream>
using namespace std;

But If you put it inside the main function, it still works. I just followed his flow of the program.

heh, dont worry I didnt cut and paste that. I just typed it real fast. Ive been told to put "using namespace std" right after the include statement, i'll try it the other way.

hey! I put "using namespace std:" inside of the main function and it compiled perfectly! Luckily I havent been using a tutorial for MSVisual C++ 6, just C++ general, so I shouldent run into any miscompatibilities, should I? The tutorial id written for Windows users and recommends Borland. I hope Borland isnt as bad as Visual.