Mine

#include <cstdio>
#include <GL/glx.h>

int main() {
	int attrib[10] = {GLX_RED_SIZE, 5, GLX_GREEN_SIZE, 5, GLX_BLUE_SIZE, 5, None};
	int a;
	Display *d = XOpenDisplay(NULL);
	GLXFBConfig *fb = glXChooseFBConfig(d, 0, attrib, &a);
	if (!fb) {
		printf("Dammit\n");
	}
	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, 1024, 512, 0, GL_BGRA, GL_UNSIGNED_BYTE, 0);
	GLenum err = glGetError();
	if (err == GL_INVALID_VALUE) {
		printf("Crap\n");
	}
}