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32 .\" @(#)adjtime.2 8.1 (Berkeley) 6/4/93
33 .\" $FreeBSD: src/lib/libc/sys/adjtime.2,v 1.6.2.4 2001/12/14 18:34:00 ru Exp $
34 .\" $DragonFly: src/lib/libc/sys/adjtime.2,v 1.2 2003/06/17 04:26:47 dillon Exp $
41 .Nd "correct the time to allow synchronization of the system clock"
47 .Fn adjtime "const struct timeval *delta" "struct timeval *olddelta"
50 makes small adjustments to the system time, as returned by
52 advancing or retarding it
53 by the time specified by the timeval
57 is negative, the clock is
58 slowed down by incrementing it more slowly than normal until
59 the correction is complete.
62 is positive, a larger increment than normal
64 The skew used to perform the correction is generally a fraction of one percent.
65 Thus, the time is always
66 a monotonically increasing function.
67 A time correction from an earlier call to
69 may not be finished when
75 the structure pointed to will contain, upon return, the
76 number of microseconds still to be corrected
77 from the earlier call.
79 This call may be used by time servers that synchronize the clocks
80 of computers in a local area network.
81 Such time servers would slow down the clocks of some machines
82 and speed up the clocks of others to bring them to the average network time.
86 is restricted to the super-user.
94 An argument points outside the process's allocated address space.
96 The process's effective user ID is not that of the super-user.
104 .%T "TSP: The Time Synchronization Protocol for UNIX 4.3BSD"
111 function call appeared in