DATE(1) - General Commands Manual # DATE(1) - General Commands Manual
NAME # date - display or set date and time
SYNOPSIS # date [-aju] [-f pformat] [-r seconds] [-z output_zone] [+‌format] [[[[[[cc]yy]mm]dd]HH]MM[.SS]]
DESCRIPTION # When invoked without arguments, the date utility displays the current date and time. Otherwise, depending on the options specified, date will set the date and time or print it in a user-defined way.
Changing the system date has some risks, as described in settimeofday(2).
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NTPD(8) - System Manager’s Manual # NTPD(8) - System Manager’s Manual
NAME # ntpd - Network Time Protocol (NTP) daemon
SYNOPSIS # ntpd [-dnv] [-f file]
DESCRIPTION # The ntpd daemon synchronizes the local clock to one or more remote NTP servers or local timedelta sensors. ntpd can also act as an NTP server itself, redistributing the local time. It implements the Simple Network Time Protocol version 4, as described in RFC 5905, and the Network Time Protocol version 3, as described in RFC 1305.
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RDATE(8) - System Manager’s Manual # RDATE(8) - System Manager’s Manual
NAME # rdate - set the system’s date from a remote host
SYNOPSIS # rdate [-46acnopsv] host
DESCRIPTION # rdate displays and sets the local date and time from the host name or address given as the argument. The time source may be an RFC 5905 protocol SNTP/NTP server or an RFC 868 TCP protocol server, which is usually implemented as a built-in service of inetd(8).
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