you can create dialog windows called "prompts" which have a message and some buttons...

[chaz/openbox] / data / xbm / close.xbm

#define close_width 6
#define close_height 6
static unsigned char close_bits[] = {
   0x33, 0x3f, 0x1e, 0x1e, 0x3f, 0x33 };