#define PROMPT_BUFSIZE 256

#define X_ENTER_KEY   36
#define X_BACKSPACE   22
#define X_ESCAPE_KEY  9

#define X_Q_KEY     24
#define X_W_KEY     25
#define X_E_KEY     26

#define X_A_KEY     38
#define X_S_KEY     39
#define X_D_KEY     40

#define TEXT_CORNER_OFFSET 25

typedef struct {
  Window window; 
  Display *display;
  Colormap colormap;
  XColor background;
  XColor foreground;
  unsigned int channel_step;
} update_info;