Simple example of raylib rendering whatever is coming on stdin

raylib_stdin_sink.c

#include <stdio.h>
#include <stdlib.h>
#include <threads.h>

#include "raylib.h"
#include "rlgl.h"

int main(int argc, char **argv)
{
	if (argc != 4) {
		fprintf(stderr, "usage: %s width height fps\n", argv[0]);
		fprintf(stderr, "0 or negative number for fps means best effort\n");
		exit(EXIT_FAILURE);
	}

	int w = atoi(argv[1]);
	int h = atoi(argv[2]);
	int target_fps = atoi(argv[3]);

	if (w <= 0 || h <= 0) {
		fprintf(stderr, "error: invalid window dimensions\n");
		exit(EXIT_FAILURE);
	}

	InitWindow(w, h, "raylib sink");
	if (target_fps > 0) {
		SetTargetFPS(target_fps);
		fprintf(stderr, "Target FPS set to %d\n", target_fps);
	} else {
		fprintf(stderr, "Rendering with best effort\n");
	}

	BeginDrawing();
		ClearBackground(DARKBLUE);
		DrawTextEx(GetFontDefault(), "Please wait warmly...", (Vector2){2,0}, 20, 2, LIGHTGRAY); 
	EndDrawing();
	thrd_sleep(&(struct timespec){.tv_sec=1}, NULL);

	size_t rgb_buf_sz = w*h*3;
	char *rgb_buf = malloc(rgb_buf_sz);
	if (!rgb_buf) {
		fprintf(stderr, "error: memory allocation problem\n");
		exit(EXIT_FAILURE);
	}
	PixelFormat px_fmt = PIXELFORMAT_UNCOMPRESSED_R8G8B8;
	Texture2D rgb_tex = {
		.id = rlLoadTexture(rgb_buf, w, h, px_fmt, 1),
		.width = w,
		.height = h,
		.mipmaps = 1,
		.format = px_fmt,
	};

	while (!WindowShouldClose()) {
		// Update
		if (fread(rgb_buf, rgb_buf_sz, 1, stdin) != 1) {
			if (!feof(stdin)) {
				fprintf(stderr, "error: reading problem\n");
				exit(EXIT_FAILURE);
			} else {
				fprintf(stderr, "EOF\n");
				exit(EXIT_SUCCESS);
			}
		}
		UpdateTexture(rgb_tex, rgb_buf);

		// Draw
		BeginDrawing();
			DrawTexture(rgb_tex, 0, 0, WHITE);
			DrawFPS(10, 10);
		EndDrawing();
	}

	free(rgb_buf);
	UnloadTexture(rgb_tex);
	CloseWindow();
	return 0;
}