CENTISEC2MSEC
peer_adver_int = CENTISEC2MSEC(ntohs(vp->vp_rsvd_adver_int) & 0x0fff);
#define VRRP_MAX_ADVER_INT_MIN CENTISEC2MSEC(1)
#define VRRP_MAX_ADVER_INT_MAX CENTISEC2MSEC(4095) /* (2^12 -1) */
#define VRRP_MAX_ADVER_INT_DFLT CENTISEC2MSEC(100) /* 1 sec */