This is tool to ping multiple ip and say the first ip in list up

associated with route to an ip via a specific gateway, it allow check if path via an ISP is UP
Why just not do bash script for each gateway?
 - Have the event on gateway change
 - Prevent complicated route gateway parse
 - Just transmit the UP ip and deduce the working gateway to update dns

This software do ping via icmp and epoll. No thread. Checked by memory check (valgrind). Good performance (minimal computing, no timming and other not used stuff).
Oriented on IPv4 public fixed ip for multihoming. Compatible with C99, C11 and maybe the last C standard

When change detected, call "up.sh" into current folder