mkdir testdir
Download putty from http://www.columbia.edu/acis/software/putty/. You may have to enter your uni and password to download it.
Goto Programs → Putty → Cunix.
Enter your uni for login and then enter your password. Once you login, you will see a $ on the left of your screen.
Create or make a directory called testdir by typing:
mkdir testdir
Change the current directory to testdir by typing:
cd testdir
Now open a file sum.c with the emacs editor
emacs sum.c
Type in your program
#include<stdio.h>
main()
{
int x, y, z;
printf ("Enter the value of x: ");
scanf ("%d", &x);
printf ("Enter the value of y: ");
scanf ("%d", &y);
z = x + y;
printf ("The sum is %d\n", z);
}
Save the program using
Ctr-x Ctr-s
Exit from the editor using
Ctr-x Ctr-c
You should now see the $ sign (may appear on the bottom-left of your screen).
Now compile your program by typing
gcc -o sum sum.c
And then run your program by typing
./sum
For more information on emacs, see http://www1.cs.columbia.edu/~bert/courses/1003/cunix.html#Editors
Happy Programming!