I tried to compile a program I am developing but it complains about gl3.h being missing. i have searched all over but cannot find it. Even here on the opengl site there is a link to it but it is a dead link.
Any idea how I can resolve this please?
Code :
 
#include <stdio.h>
#include <stdlib.h>
/* If using gl3.h */
/* Ensure we are using opengl's core profile only */
#define GL3_PROTOTYPES 1
#include <GL/gl3.h>
 
#include <SDL.h>
#define PROGRAM_NAME "Tutorial1"
 
/* A simple function that prints a message, the error code returned by SDL,
 * and quits the application */
void sdldie(const char *msg)
{
    printf("%s: %s\n", msg, SDL_GetError());
    SDL_Quit();
    exit(1);
}
 
 
void checkSDLError(int line ) /*= -1)*/
{
#ifndef NDEBUG
        const char *error = SDL_GetError();
        if (*error != '\0')
        {
                printf("SDL Error: %s\n", error);
                if (line != -1)
                        printf(" + line: %i\n", line);
                SDL_ClearError();
        }
#endif
}
 
 
/* Our program's entry point */
int main(int argc, char *argv[])
{
    SDL_Window *mainwindow; /* Our window handle */
    SDL_GLContext maincontext; /* Our opengl context handle */
 
    if (SDL_Init(SDL_INIT_VIDEO) < 0) /* Initialize SDL's Video subsystem */
        sdldie("Unable to initialize SDL"); /* Or die on error */
 
    /* Request opengl 3.2 context.
     * SDL doesn't have the ability to choose which profile at this time of writing,
     * but it should default to the core profile */
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 2);
 
    /* Turn on double buffering with a 24bit Z buffer.
     * You may need to change this to 16 or 32 for your system */
    SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
    SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 24);
 
    /* Create our window centered at 512x512 resolution */
    mainwindow = SDL_CreateWindow(PROGRAM_NAME, SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED,
        512, 512, SDL_WINDOW_OPENGL | SDL_WINDOW_SHOWN);
    if (!mainwindow) /* Die if creation failed */
        sdldie("Unable to create window");
 
    checkSDLError(__LINE__);
 
    /* Create our opengl context and attach it to our window */
    maincontext = SDL_GL_CreateContext(mainwindow);
    checkSDLError(__LINE__);
 
 
    /* This makes our buffer swap syncronized with the monitor's vertical refresh */
    SDL_GL_SetSwapInterval(1);
 
    /* Clear our buffer with a red background */
    glClearColor ( 1.0, 0.0, 0.0, 1.0 );
    glClear ( GL_COLOR_BUFFER_BIT );
    /* Swap our back buffer to the front */
    SDL_GL_SwapWindow(mainwindow);
    /* Wait 2 seconds */
    SDL_Delay(2000);
 
    /* Same as above, but green */
    glClearColor ( 0.0, 1.0, 0.0, 1.0 );
    glClear ( GL_COLOR_BUFFER_BIT );
    SDL_GL_SwapWindow(mainwindow);
    SDL_Delay(2000);
 
    /* Same as above, but blue */
    glClearColor ( 0.0, 0.0, 1.0, 1.0 );
    glClear ( GL_COLOR_BUFFER_BIT );
    SDL_GL_SwapWindow(mainwindow);
    SDL_Delay(2000);
 
    /* Delete our opengl context, destroy our window, and shutdown SDL */
    SDL_GL_DeleteContext(maincontext);
    SDL_DestroyWindow(mainwindow);
    SDL_Quit();
 
    return 0;
}

I am trying to compile it with
Code :
gcc tut1.c  -lGL $(sdl-config --cflags --libs)