find_next_free_x_display.py

#!/usr/bin/python

def find_next_free_x_display():
    for i in range(10):
        try_path = "/tmp/.X" + str(i) + "-lock"
        try:
            with open(try_path,"r"):
                print("-- " + str(i) + " is there")
        except:
           return i
    else:
        return -1

print(find_next_free_x_display())