Split Screen OpenGL

[0x4B47]

Hi fellow coders,

I am trying to get a split screen effect in OpenGL but only the 2nd viewport displays, from the code, can anyone tell me what I'm doing wrong?

#include <GL/glut.h>
#include <stdlib.h>

void init(void)
{
	glClearColor(0.0, 0.0, 0.0, 0.0);
}

void display(void)
{
	glClear(GL_COLOR_BUFFER_BIT);
	glColor3f(1.0,1.0,1.0);
	glBegin(GL_LINES);
		glVertex2i(100,100);
		glVertex2i(200,200);
	glEnd();
	glFlush();
}

void reshape(int w, int h)
{
	glViewport(0, 0, (GLsizei)w/2, (GLsizei)h);
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	gluOrtho2D(0.0, (GLdouble)w, 0.0, (GLdouble)h);
	glMatrixMode(GL_MODELVIEW);
	
	glViewport((GLsizei)w/2, 0, (GLsizei)w/2, (GLsizei)h);
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	gluOrtho2D(0.0, (GLdouble)w, 0.0, (GLdouble)h);
	glMatrixMode(GL_MODELVIEW);
}

int main(int argc, char** argv)
{
	glutInit(&argc, argv);
	glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
	glutInitWindowSize(800, 600);
	glutInitWindowPosition(100, 100);
	glutCreateWindow(&quot;Split Screen Viewport&quot;);
	init();
	glutDisplayFunc(display);
	glutReshapeFunc(reshape);
	glutMainLoop();

	return 0;
}

Thanks,
K.