HowTo: Compile And Run a C/C++ Code In Linux

I am a new Linux user and student who used to write C or C++ programs on MS-Windows. Now, I am using Ubuntu Linux. How can I compile a C or C++ program on Linux operating systems using bash Terminal application?

To compile a C or C++ program on any Linux distro such as Ubuntu, Red Hat, Fedora, Debian and other Linux distro you need to install:

1. GNU C and C++ compiler collection
2. Development tools
3. Development libraries
4. IDE or text editor to write programs

Step #1: Install C/C++ compiler and related tools

If you are using Fedora, Red Hat, CentOS, or Scientific Linux, use the following yum command to install GNU c/c++ compiler:
# yum groupinstall 'Development Tools'
If you are using Debian or Ubuntu Linux, type the following apt-get command to install GNU c/c++ compiler:
$ sudo apt-get update
$ sudo apt-get install build-essential manpages-dev

Step #2: Verify installation

Type the following command to display the version number and location of the compiler on Linux:
$ whereis gcc
$ which gcc
$ gcc --version
Sample outputs:

Fig. 01: GNU C/C++ compilers on Linux

How to Compile and Run C/C++ program on Linux

Create a file called demo.c using a text editor such as vi, emacs or joe:

#include<stdio.h>
/* demo.c:  My first C program on a Linux */
int main(void)
{
 printf("Hello! This is a test prgoram.\n");
 return 0;
}
 

How do I compile the program on Linux?

Use any one of the following syntax to compile the program called demo.c:

 
cc program-source-code.c -o executable-file-name
 

OR

 
gcc program-source-code.c -o executable-file-name
 

OR

## assuming that executable-file-name.c exists ##
make executable-file-name
 

In this example, compile demo.c, enter:

 
cc     demo.c   -o demo
 

OR

## assuming demo.c exists in the current directory ##
make demo
 

If there is no error in your code or C program then the compiler will successfully create an executable file called demo in the current directory, otherwise you need fix the code. To verify this, type:
$ ls -l demo*

How do I run or execute the program called demo on Linux?

Simply type the the program name:
$ ./demo
OR
$ /path/to/demo
Samples session:

Animated gif 01: Compile and run C and C++ program demo

Compiling and running a simple C++ program

Create a program called demo2.C as follows:

#include "iostream"
// demo2.C - Sample C++ prgoram 
int main(void)
{
    std::cout << "Hello! This is a C++ program.\n";
    return 0;
}

To compile this program, enter:

 
g++ demo2.C -o demo2
## or use the following syntax ##
make demo2
 

To run this program, type:

 
./demo2
 

How do I generate symbolic information for gdb and warning messages?

The syntax is as follows C compiler:
cc -g -Wall input.c -o executable
The syntax is as follows C++ compiler:
g++ -g -Wall input.C -o executable

How do I generate optimized code on a Linux machine?

The syntax is as follows C compiler:
cc -O input.c -o executable
The syntax is as follows C++ compiler:
g++ -O -Wall input.C -o executable

How do I compile a C program that uses math functions?

The syntax is as follows when need pass the -lm option with gcc to link with the math libraries:
cc myth1.c -o executable -lm

How do I compile a C++ program that uses Xlib graphics functions?

The syntax is as follows when need pass the -lX11 option with gcc to link with the Xlib libraries:
g++ fireworks.C -o executable -lX11

How do I compile a program with multiple source files?

The syntax is as follows if the source code is in several files (such as light.c, sky.c, fireworks.c):
cc light.c sky.c fireworks.c -o executable
C++ syntax is as follows if the source code is in several files:
g++ ac.C bc.C file3.C -o my-program-name

See gcc(1) Linux and Unix man page for more information.