Retrieve the current value of the specified window property of type void*
#include <screen/screen.h>
int screen_get_window_property_pv(screen_window_t win, int pname, void **param)
Function Type: Flushing Execution
Note [1]: When you're retrieving this property, the function type is Immediate Execution.
Note [2]: When you're retrieving this property, Screen locally allocates resources to track the object that you retrieve. Therefore, you must call the appropriate screen_destroy_*() function to free these resources when you no longer need to use the object in your local context.
0 if successful, or -1 if an error occurred (errno is set; refer to errno.h for more details).