SDL Shows blank window like it has crashed - c

Question

When i build my program, i get this output:
https://i.stack.imgur.com/8zdq5.png][1]
here is the code for creating the window:
main.c:
#include <SDL2/SDL.h>
#include <SDL2/SDL_image.h>
#include "RenderWindow.h"
int main(int argc, char *args[])
{
if(SDL_Init(SDL_INIT_VIDEO) > 0)
printf("ERROR: %s",SDL_GetError());
if(!IMG_Init(IMG_INIT_PNG))
printf("ERROR: %s",SDL_GetError());
CreateWindow("M64!", 1280, 720);
int gameRunning = 1;
SDL_Event event;
while(gameRunning == 1){
while(SDL_PollEvent(&event)){
if(event.type == SDL_QUIT)
gameRunning = 0;
}
}
cleanUp();
SDL_Quit();
return 0;
}
Here is RenderWindow.h:
#ifndef RENDERWINDOW_H
#define RENDERWINDOW_H
#include <SDL2/SDL.h>
#include <SDL2/SDL_image.h>
int CreateWindow(const char* title, int p_w, int p_h);
int RenderWindow();
void cleanUp();
SDL_Window* window;
SDL_Renderer* renderer;
#endif
And here is RenderWindow.c:
#include <SDL2/SDL.h>
#include <SDL2/SDL_image.h>
#include <stdio.h>
#include "RenderWindow.h"
int CreateWindow(const char* title, int p_w, int p_h)
{
window = SDL_CreateWindow(title, SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, p_w, p_h, SDL_WINDOW_SHOWN);
if(window == NULL)
printf("ERROR: %s", SDL_GetError());
renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED);
return 0;
}
void cleanUp()
{
SDL_DestroyWindow(window);
}
Is this a software issue, or is it a hardware one? cause my PC is pretty old.
Edit:This is solved, for anyone having the same question the answer to this is is that you have to write: SDL_RenderClear(your_renderer); and SDL_RenderPresent(your_renderer); where the first one clears the renderer, and the second one updates it