View Full Version : Can't Compile C program

March 1st, 2007, 12:47 PM
Hi guys , I am new to Ubuntu Linux (just installed it yesterday) . so i tried writing this Hello World Program and i got these errors when i tried to compile it using gcc

hello.c:1:19: error: stdio.h: No such file or directory
hello.c: In function ‘main’:
hello.c:5: warning: incompatible implicit declaration of built-in function ‘printf’

My program looks fine

#include <stdio.h>

int main()
printf("Hello, world\n");
return 0;

can you guys help me out !! thanks a lot


March 1st, 2007, 01:08 PM
You need to install the programming packages. Do this once:

sudo aptitude install build-essential

March 1st, 2007, 01:14 PM
Looks like your compiler wasn't installed properly, or somethings screwie with you environment...

Do you have the directory /usr/include and can you find stdio.h in it?
What happens if you run:
> cpp hello.c

and what about

> cpp --sysroot=/ hello.c


March 1st, 2007, 01:56 PM
Thank you AstalaVista

now its working

can i know what does

sudo aptitude install build-essential

actually do ?

March 1st, 2007, 02:01 PM
Thank you AstalaVista

now its working

can i know what does

actually do ?
"sudo" raises your privileges to allow admin tasks.
"aptitude" is one of the program ways to handle installing packages on Ubuntu.
"install", obvious :)
"build-essential" is the name of the package. It includes headers and certain other files essential for building stuff.

P.S. This is not meant as a Sarcastic post, having read it back it could come across that way.

February 16th, 2008, 09:43 PM
maybe a stupid question:
how do i run the a.out that i get out of it?


February 16th, 2008, 09:47 PM

That will work if you are in the directory the a.out file is in (note: this is run from the terminal).

February 16th, 2008, 09:53 PM
StevenRoose3: see FAQ: Compiling your first C program (http://ubuntuforums.org/showthread.php?t=689635)