This example shows you how to create a Hello World application with having the logic of hello world in a separate C++ files called hello.h the header file and hello.cpp the implementation file.<\/p>\n\n\n\n
Let’s start coding. However you can find following code here in My C++ Tutorial<\/a> in Github.<\/p>\n\n\n\n First make sure gcc is installed on your machine. g++ command will be installed as a part of gcc package.<\/p>\n\n\n\n If gcc and g++ are installed correctly, you should be able to check their version using following commands:<\/p>\n\n\n\n The first step is create the header file called hello.h<\/strong> . The hello.h header file contains only one line which describes the hello() function signature in abstract level. Make sure hello.h contains following line:<\/p>\n\n\n\nhello.h<\/b>\n After that create hello.cpp<\/strong> which is the implementation of hello.h header file. There you need to implement hello() function that contains body:<\/p>\n\n\n\nhello.cpp<\/b>\n The last part is creating main.cpp<\/strong> file which in this file you call hello() function that you implemented in hello.cpp. That prints Hello World!<\/strong><\/em> in the output.<\/p>\n\n\n\nmain.cpp<\/b>\n Now it's time to compile your source code and make it executable. For compiling C source codes you can use gcc command, but for C++ source codes, you need to use g++ compiler command. Here are the instruction to compile the files you have just created to Hello World application.<\/p>\n\n\n\n Using -c you can compile your shared library that typically it shouldn't be executable and having main method. Here is an example:<\/p>\n\n\n\n The output will be hello.o<\/strong> file. Now, use following g++ with -o option to specify the executable file name you want to run and also add hello.o shared library file, so that g++ compiler link all files into one executable file called greet.<\/p>\n\n\n\n Finally, you can run your compile greet app using following command:<\/p>\n\n\n\n$ g++ --version\nConfigured with: --prefix=\/Library\/Developer\/CommandLineTools\/usr --with-gxx-include-dir=\/Library\/Developer\/CommandLineTools\/SDKs\/MacOSX10.14.sdk\/usr\/include\/c++\/4.2.1\nApple LLVM version 10.0.1 (clang-1001.0.46.4)\nTarget: x86_64-apple-darwin18.2.0\nThread model: posix\nInstalledDir: \/Library\/Developer\/CommandLineTools\/usr\/bin\n\n$ gcc --version\nConfigured with: --prefix=\/Library\/Developer\/CommandLineTools\/usr --with-gxx-include-dir=\/Library\/Developer\/CommandLineTools\/SDKs\/MacOSX10.14.sdk\/usr\/include\/c++\/4.2.1\nApple LLVM version 10.0.1 (clang-1001.0.46.4)\nTarget: x86_64-apple-darwin18.2.0\nThread model: posix\nInstalledDir: \/Library\/Developer\/CommandLineTools\/usr\/bin\n<\/pre>\n\n\n\n
void hello();<\/pre>\n\n\n\n
\n#include
#include \"hello.h\"\n\nint main (void){\n hello();\n}\n<\/pre>\n\n\n\n$ g++ -c hello.cpp<\/pre>\n\n\n\n
$ g++ -o greet main.cpp hello.o<\/pre>\n\n\n\n
$ .\/greet\nHello World!\n<\/pre>\n\n\n\n