Utilice la API de XRandr (man 3 Xrandr). Vea aquí un ejemplo:
- http://www.blitzbasic.com/Community/posts.php?topic=86911
También puede consultar el código de xrandr(1).
Edit1:Por el bien de la posteridad:
Código de muestra ligeramente ajustado para que sea más una demostración:
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <string>
#include <iostream>
#include <unistd.h>
#include <X11/Xlib.h>
#include <X11/extensions/Xrandr.h>
int main()
{
int num_sizes;
Rotation current_rotation;
Display *dpy = XOpenDisplay(NULL);
Window root = RootWindow(dpy, 0);
XRRScreenSize *xrrs = XRRSizes(dpy, 0, &num_sizes);
//
// GET CURRENT RESOLUTION AND FREQUENCY
//
XRRScreenConfiguration *conf = XRRGetScreenInfo(dpy, root);
short current_rate = XRRConfigCurrentRate(conf);
SizeID current_size_id = XRRConfigCurrentConfiguration(conf, ¤t_rotation);
int current_width = xrrs[current_size_id].width;
int current_height = xrrs[current_size_id].height;
std::cout << "current_rate = " << current_rate << std::endl;
std::cout << "current_width = " << current_width << std::endl;
std::cout << "current_height = " << current_height << std::endl;
XCloseDisplay(dpy);
}
Compilar con:
g++ 17797636.cpp -o 17797636 -lX11 -lXrandr
Salida:
$ ./17797636
current_rate = 50
current_width = 1920
current_height = 1080