+++ /dev/null
-.\" Copyright (c) 2006 by Michael Kerrisk <mtk.manpages@gmail.com>
-.\"
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-.\" manual under the conditions for verbatim copying, provided that the
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-.\"
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-.\" the use of the information contained herein. The author(s) may not
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-.\" professionally.
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-.\"
-.TH ADJTIME 3 2014-05-28 "Linux" "Linux Programmer's Manual"
-.SH NAME
-adjtime \- correct the time to synchronize the system clock
-.SH SYNOPSIS
-.nf
-.B #include <sys/time.h>
-.sp
-.BI "int adjtime(const struct timeval *" delta ", struct timeval *" olddelta );
-.fi
-.sp
-.in -4n
-Feature Test Macro Requirements for glibc (see
-.BR feature_test_macros (7)):
-.in
-.sp
-.BR adjtime ():
-_BSD_SOURCE
-.SH DESCRIPTION
-The
-.BR adjtime ()
-function gradually adjusts the system clock (as returned by
-.BR gettimeofday (2)).
-The amount of time by which the clock is to be adjusted is specified
-in the structure pointed to by
-.IR delta .
-This structure has the following form:
-.in +4n
-.nf
-
-struct timeval {
- time_t tv_sec; /* seconds */
- suseconds_t tv_usec; /* microseconds */
-};
-.fi
-.in
-.PP
-If the adjustment in
-.I delta
-is positive, then the system clock is speeded up by some
-small percentage (i.e., by adding a small
-amount of time to the clock value in each second) until the adjustment
-has been completed.
-If the adjustment in
-.I delta
-is negative, then the clock is slowed down in a similar fashion.
-
-If a clock adjustment from an earlier
-.BR adjtime ()
-call is already in progress
-at the time of a later
-.BR adjtime ()
-call, and
-.I delta
-is not NULL for the later call, then the earlier adjustment is stopped,
-but any already completed part of that adjustment is not undone.
-
-If
-.I olddelta
-is not NULL, then the buffer that it points to is used to return
-the amount of time remaining from any previous adjustment that
-has not yet been completed.
-.SH RETURN VALUE
-On success,
-.BR adjtime ()
-returns 0.
-On failure, \-1 is returned, and
-.I errno
-is set to indicate the error.
-.SH ERRORS
-.TP
-.B EINVAL
-The adjustment in
-.I delta
-is outside the permitted range.
-.TP
-.B EPERM
-The caller does not have sufficient privilege to adjust the time.
-Under Linux, the
-.B CAP_SYS_TIME
-capability is required.
-.SH ATTRIBUTES
-.SS Multithreading (see pthreads(7))
-The
-.BR adjtime ()
-function is thread-safe.
-.SH CONFORMING TO
-4.3BSD, System V.
-.SH NOTES
-The adjustment that
-.BR adjtime ()
-makes to the clock is carried out in such a manner that the clock
-is always monotonically increasing.
-Using
-.BR adjtime ()
-to adjust the time prevents the problems that can be caused for certain
-applications (e.g.,
-.BR make (1))
-by abrupt positive or negative jumps in the system time.
-
-.BR adjtime ()
-is intended to be used to make small adjustments to the system time.
-Most systems impose a limit on the adjustment that can be specified in
-.IR delta .
-In the glibc implementation,
-.I delta
-must be less than or equal to (INT_MAX / 1000000 \- 2)
-and greater than or equal to (INT_MIN / 1000000 + 2)
-(respectively 2145 and \-2145 seconds on i386).
-.SH BUGS
-A longstanding bug
-.\" http://sourceware.org/bugzilla/show_bug?id=2449
-.\" http://bugzilla.kernel.org/show_bug.cgi?id=6761
-meant that if
-.I delta
-was specified as NULL,
-no valid information about the outstanding clock adjustment was returned in
-.IR olddelta .
-(In this circumstance,
-.BR adjtime ()
-should return the outstanding clock adjustment, without changing it.)
-This bug is fixed
-.\" Thanks to the new adjtimex() ADJ_OFFSET_SS_READ flag
-on systems with glibc 2.8 or later and
-Linux kernel 2.6.26 or later.
-.SH SEE ALSO
-.BR adjtimex (2),
-.BR gettimeofday (2),
-.BR time (7)
-.SH COLOPHON
-This page is part of release 3.79 of the Linux
-.I man-pages
-project.
-A description of the project,
-information about reporting bugs,
-and the latest version of this page,
-can be found at
-\%http://www.kernel.org/doc/man\-pages/.
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