How to add paths in ubuntu

Question

I know that this is a very popular question with a lot of threads already about it, but unfortunately after trying some of the suggestions I didn't manage to solve my problem, so I am posting a new question about it. What I am interested in, is running a c++ program in terminal, the thing is, as I was always using eclipse to compile and run programs I am completely noob on this and also my ubuntu knowledge is limitated to very basic things. So what I am finding difficulties in is when I want to compile a program which needs to include some header files form different directories. What I want to do is to include this libraries without needing to add in the #include "..." the whole path of where the library is but just it's name. In Eclipse this could be done by adding paths through options, but in Ubuntu I am not really sure how to do so, following some instructions in other threads I tried to add the paths to my ~/.profile txt file but without any success. So I would like to ask how is this possible to be done, i.e. where and how to add the paths of the header files needed so that I want have all the time for very new project to provide the entire path in my includes.

Answer 1

You add the path with -I arguments to g++ for example,

$ cat /home/efrisch/t/myheader.h
#include <iostream>
$ cat hello.cc
#include "myheader.h"

int main(int argc, char **argv) {
    std::cout << "Hello, World!" << std::endl;
}
$ g++ -O -I/home/efrisch/t hello.cc -o hello
$ ./hello
Hello, World!