Network Time Protocol - sntp client

 NTP, the Network Time Protocol, is used to keep computer clocks
 accurate by synchronizing them over the Internet or a local network,
 or by following an accurate hardware receiver that interprets GPS,
 DCF-77, NIST or similar time signals.
 .
 sntp can be used as an SNTP client to query a NTP or SNTP server and
 either display the time or set the local system's time. It is not
 sufficient, however, for maintaining an accurate clock in the long run.