View Full Version : [SOLVED] Compiling c++ program

Despot Despondency
November 13th, 2008, 08:44 PM
Hi, I just started learning c++ and I'm trying to compile the following program

#include <iostream>

int main()
std::cout << "Hello, world!" << std::endl;
return 0;

Now when I try

gcc -o helloWorld helloWorld.c

I get the following error

helloWorld.c:1:20: error: iostream: No such file or directory
helloWorld.c: In function ‘main’:
helloWorld.c:5: error: expected expression before ‘:’ token

I have gcc and build-essential already installed and I've tried using <iostream.h> instead of <iostream>, but to no avail. Any help would be appreciated.

November 13th, 2008, 08:52 PM
Your code, you need to do one of two things. Make the header file:

#include <iostream.h>
or include the standard namespace globally, ie:

#include <iostream>
using namespace std;

November 13th, 2008, 08:55 PM
g++ -o hello ./hello.cppnot
gcc -o hello ./hello.cppgcc is the gcc compiler.

November 13th, 2008, 08:59 PM
g++ -o hello ./hello.cppnot
gcc -o hello ./hello.cppgcc is the gcc compiler.

Hahaha, yup that would solve the problem too. Good eye, cmay

November 13th, 2008, 09:04 PM
use g++ to compile c++ source files - check this link:

Hope this helps a bit.

(who appears to be too slow this pm)

November 13th, 2008, 09:10 PM
Also, not that this would matter too much on how things will work, but your file seems to have a C file extension (.c), rather than the C++ extension (.cpp). But again, that would not affect your error message, but it is good practice to keep good file extensions, especially if you have a project that combines both C and C++ together.

November 13th, 2008, 09:17 PM
Took me a couple of minutes to remember - but an alternative is to include the stdc++
lib on the command line as an option:

steveo@delldesktop:~$ gcc hw.cpp -o hello -lstdc++
steveo@delldesktop:~$ ./hello
Hello, world!

(BTW, If I recall correctly, the use of iostream.h is deprecated -
I do very little compiled language programming anymore)

Despot Despondency
November 13th, 2008, 09:29 PM
Hi, thanks everyone. I didn't realize that c++ programs had to be compiled with the g++ command and not gcc. Cheers again.