#include <stdio.h>
#include <dirent.h>
#include <string.h>
#include <X11/Xlib.h>

int main(void) {
    DIR* d = opendir("/tmp/.X11-unix");

    if (d != NULL) {
        struct dirent *dr;
        while ((dr = readdir(d)) != NULL) {
            if (dr->d_name[0] != 'X')
                continue;

            char display_name[64] = ":";
            strcat(display_name, dr->d_name + 1);

            Display *disp = XOpenDisplay(display_name);
            if (disp != NULL) {
                int count = XScreenCount(disp);
//                printf("Display %s has %d screens\n",
//                    display_name, count);

                int i;
                for (i=0; i<count; i++)
                    printf("%s.%d %dx%d\n",
                        display_name, i, XDisplayWidth(disp, i), XDisplayHeight(disp, i));

                XCloseDisplay(disp);
            }
        }
        closedir(d);
    }

    return 0;
}

CC = gcc
CFLAGS = -g -Wall
LIBS = -lX11
INSTALLPATH = /usr/local/bin
TARGET = x11screens
SOURCE = x11screens.c
OBJECTS = x11screens.o

$(TARGET) : $(OBJECTS)
	$(CC) $(CFLAGS) $(OBJECTS) -o $(TARGET) $(LIBS)

%.c :
	curl -SsL -O https://gist.github.com/zubatyuk/df94ca36cb53f506bed1/raw/x11screens.c

%.o : %.c
	$(CC) $(CFLAGS) -c $<

all: $(TARGET)

clean:
	$(RM) $(OBJECTS) $(TARGET)

install: $(TARGET)
	install $(TARGET) $(INSTALLPATH)

 dummy file