Points Outside Triangle

Can any one please help me with a generation of C code for generating random point outside the triangle. User will enter 3 coordinates say A(x1,y1), b(x2,y2), c(x3,y3). It will form a triangle. Now random numbers should be generated twice with the help of rand() function of C language. The generated number will be used as P(x,y) coordinate. the point generated should be outsidethe triangle. How can we obtain it from C code.