Adding upstream version 4.5.upstream/4.5

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 278 insertions, 0 deletions

diff --git a/doc/chronyd.man.in b/doc/chronyd.man.in
new file mode 100644
index 0000000..96e87a0
--- /dev/null
+++ b/doc/chronyd.man.in
@@ -0,0 +1,278 @@
+'\" t
+.\"     Title: chronyd
+.\"    Author: [see the "AUTHOR(S)" section]
+.\" Generator: Asciidoctor 2.0.20
+.\"      Date: 2023-12-05
+.\"    Manual: System Administration
+.\"    Source: chrony @CHRONY_VERSION@
+.\"  Language: English
+.\"
+.TH "CHRONYD" "8" "2023-12-05" "chrony @CHRONY_VERSION@" "System Administration"
+.ie \n(.g .ds Aq \(aq
+.el       .ds Aq '
+.ss \n[.ss] 0
+.nh
+.ad l
+.de URL
+\fI\\$2\fP <\\$1>\\$3
+..
+.als MTO URL
+.if \n[.g] \{\
+.  mso www.tmac
+.  am URL
+.    ad l
+.  .
+.  am MTO
+.    ad l
+.  .
+.  LINKSTYLE blue R < >
+.\}
+.SH "NAME"
+chronyd \- chrony daemon
+.SH "SYNOPSIS"
+.sp
+\fBchronyd\fP [\fIOPTION\fP]... [\fIDIRECTIVE\fP]...
+.SH "DESCRIPTION"
+.sp
+\fBchronyd\fP is a daemon for synchronisation of the system clock. It can
+synchronise the clock with NTP servers, reference clocks (e.g. a GPS receiver),
+and manual input using wristwatch and keyboard via \fBchronyc\fP. It can also
+operate as an NTPv4 (RFC 5905) server and peer to provide a time service to
+other computers in the network.
+.sp
+If no configuration directives are specified on the command line, \fBchronyd\fP
+will read them from a configuration file. The compiled\-in default location of
+the file is \fI@SYSCONFDIR@/chrony.conf\fP.
+.sp
+Informational messages, warnings, and errors will be logged to syslog.
+.SH "OPTIONS"
+.sp
+\fB\-4\fP
+.RS 4
+With this option hostnames will be resolved only to IPv4 addresses and only
+IPv4 sockets will be created.
+.RE
+.sp
+\fB\-6\fP
+.RS 4
+With this option hostnames will be resolved only to IPv6 addresses and only
+IPv6 sockets will be created.
+.RE
+.sp
+\fB\-f\fP \fIfile\fP
+.RS 4
+This option can be used to specify an alternate location for the configuration
+file. The compiled\-in default value is \fI@SYSCONFDIR@/chrony.conf\fP.
+.RE
+.sp
+\fB\-n\fP
+.RS 4
+When run in this mode, the program will not detach itself from the terminal.
+.RE
+.sp
+\fB\-d\fP
+.RS 4
+When run in this mode, the program will not detach itself from the terminal,
+and all messages will be written to the terminal instead of syslog. If
+\fBchronyd\fP was compiled with enabled support for debugging, this option can be
+used twice to enable debug messages.
+.RE
+.sp
+\fB\-l\fP \fIfile\fP
+.RS 4
+This option enables writing of log messages to a file instead of syslog or the
+terminal.
+.RE
+.sp
+\fB\-L\fP \fIlevel\fP
+.RS 4
+This option specifies the minimum severity level of messages to be written to
+the log file, syslog, or terminal. The following levels can be specified: \-1
+(debug, if compiled with enabled support for debugging), 0 (informational), 1
+(warning), 2 (non\-fatal error), and 3 (fatal error). The default value is 0.
+.RE
+.sp
+\fB\-p\fP
+.RS 4
+When run in this mode, \fBchronyd\fP will print the configuration and exit. It will
+not detach from the terminal. This option can be used to verify the syntax of
+the configuration and get the whole configuration, even if it is split into
+multiple files and read by the \fBinclude\fP or \fBconfdir\fP directive.
+.RE
+.sp
+\fB\-q\fP
+.RS 4
+When run in this mode, \fBchronyd\fP will set the system clock once and exit. It
+will not detach from the terminal.
+.RE
+.sp
+\fB\-Q\fP
+.RS 4
+This option is similar to the \fB\-q\fP option, except it only prints the offset
+without making any corrections of the clock and disables server ports to allow
+\fBchronyd\fP to be started without root privileges, assuming the configuration
+does not have any directives which would require them (e.g. \fBrefclock\fP,
+\fBhwtimestamp\fP, \fBrtcfile\fP, etc).
+.RE
+.sp
+\fB\-r\fP
+.RS 4
+This option will try to reload and then delete files containing sample
+histories for each of the servers and reference clocks being used. The
+files are expected to be in the directory specified by the
+\fBdumpdir\fP
+directive in the configuration file. This option is useful if you want to stop
+and restart \fBchronyd\fP briefly for any reason, e.g. to install a new version.
+However, it should be used only on systems where the kernel can maintain clock
+compensation whilst not under \fBchronyd\fP\*(Aqs control (i.e. Linux, FreeBSD, NetBSD,
+illumos, and macOS 10.13 or later).
+.RE
+.sp
+\fB\-R\fP
+.RS 4
+When this option is used, the \fBinitstepslew\fP
+directive and the \fBmakestep\fP directive used with
+a positive limit will be ignored. This option is useful when restarting
+\fBchronyd\fP and can be used in conjunction with the \fB\-r\fP option.
+.RE
+.sp
+\fB\-s\fP
+.RS 4
+This option will set the system clock from the computer\(cqs real\-time clock (RTC)
+or to the last modification time of the file specified by the
+\fBdriftfile\fP directive. Real\-time clocks are
+supported only on Linux.
+.sp
+If used in conjunction with the \fB\-r\fP flag, \fBchronyd\fP will attempt to preserve
+the old samples after setting the system clock from the RTC. This can be used
+to allow \fBchronyd\fP to perform long term averaging of the gain or loss rate
+across system reboots, and is useful for systems with intermittent access to
+network that are shut down when not in use. For this to work well, it relies
+on \fBchronyd\fP having been able to determine accurate statistics for the
+difference between the RTC and system clock last time the computer was on.
+.sp
+If the last modification time of the drift file is later than both the current
+time and the RTC time, the system time will be set to it to restore the time
+when \fBchronyd\fP was previously stopped. This is useful on computers that have no
+RTC or the RTC is broken (e.g. it has no battery).
+.RE
+.sp
+\fB\-t\fP \fItimeout\fP
+.RS 4
+This option sets a timeout (in seconds) after which \fBchronyd\fP will exit. If the
+clock is not synchronised, it will exit with a non\-zero status. This is useful
+with the \fB\-q\fP or \fB\-Q\fP option to shorten the maximum time waiting for
+measurements, or with the \fB\-r\fP option to limit the time when \fBchronyd\fP is
+running, but still allow it to adjust the frequency of the system clock.
+.RE
+.sp
+\fB\-u\fP \fIuser\fP
+.RS 4
+This option sets the name of the system user to which \fBchronyd\fP will switch
+after start in order to drop root privileges. It overrides the
+\fBuser\fP directive. The compiled\-in default value is
+\fI@DEFAULT_USER@\fP.
+.sp
+On Linux, \fBchronyd\fP needs to be compiled with support for the \fBlibcap\fP library.
+On macOS, FreeBSD, NetBSD, and illumos \fBchronyd\fP forks into two processes.
+The child process retains root privileges, but can only perform a very limited
+range of privileged system calls on behalf of the parent.
+.RE
+.sp
+\fB\-U\fP
+.RS 4
+This option disables a check for root privileges to allow \fBchronyd\fP to be
+started under a non\-root user, assuming the process will have all capabilities
+(e.g. provided by the service manager) and access to all files, directories,
+and devices, needed to operate correctly in the specified configuration. Note
+that different capabilities might be needed with different configurations and
+different Linux kernel versions. Starting \fBchronyd\fP under a non\-root user is
+not recommended when the configuration is not known, or at least limited to
+specific directives.
+.RE
+.sp
+\fB\-F\fP \fIlevel\fP
+.RS 4
+This option configures system call filters loaded by \fBchronyd\fP processes if it
+was compiled with support for the Linux secure computing (seccomp) facility.
+Three levels are defined: 0, 1, 2. The filters are disabled at level 0. At
+levels 1 and 2, \fBchronyd\fP will be killed if it makes a system call which is
+blocked by the filters. The level can be specified as a negative number to
+trigger the SIGSYS signal instead of SIGKILL, which can be useful for
+debugging. The default value is 0.
+.sp
+At level 1, the filters allow only selected system calls that are normally
+expected to be made by \fBchronyd\fP. Other system calls are blocked. This level is
+recommended only if it is known to work on the version of the system where
+\fBchrony\fP is installed. The filters need to allow also system calls made by
+libraries that \fBchronyd\fP is using (e.g. libc), but different versions or
+implementations of the libraries might make different system calls. If the
+filters are missing a system call, \fBchronyd\fP could be killed even in normal
+operation.
+.sp
+At level 2, the filters block only a small number of specific system calls
+(e.g. fork and exec). This approach should avoid false positives, but the
+protection of the system against a compromised \fBchronyd\fP process is much more
+limited.
+.sp
+The filters cannot be enabled with the \fBmailonchange\fP directive.
+.RE
+.sp
+\fB\-P\fP \fIpriority\fP
+.RS 4
+On Linux, FreeBSD, NetBSD, and illumos this option will select the SCHED_FIFO
+real\-time scheduler at the specified priority (which must be between 0 and
+100). On macOS, this option must have either a value of 0 to disable the thread
+time constraint policy or 1 for the policy to be enabled. Other systems do not
+support this option. The default value is 0.
+.RE
+.sp
+\fB\-m\fP
+.RS 4
+This option will lock \fBchronyd\fP into RAM so that it will never be paged out.
+This mode is only supported on Linux, FreeBSD, NetBSD, and illumos.
+.RE
+.sp
+\fB\-x\fP
+.RS 4
+This option disables the control of the system clock. \fBchronyd\fP will not try to
+make any adjustments of the clock. It will assume the clock is free running and
+still track its offset and frequency relative to the estimated true time. This
+option allows \fBchronyd\fP to be started without the capability to adjust or set
+the system clock (e.g. in some containers) to operate as an NTP server.
+.RE
+.sp
+\fB\-v\fP, \fB\-\-version\fP
+.RS 4
+With this option \fBchronyd\fP will print version number to the terminal and exit.
+.RE
+.sp
+\fB\-h\fP, \fB\-\-help\fP
+.RS 4
+With this option \fBchronyd\fP will print a help message to the terminal and exit.
+.RE
+.SH "ENVIRONMENT VARIABLES"
+.sp
+\fBLISTEN_FDS\fP
+.RS 4
+On Linux systems, the systemd service manager may pass file descriptors for
+pre\-initialised sockets to \fBchronyd\fP. The service manager allocates and binds
+the file descriptors, and passes a copy to each spawned instance of the
+service. This allows for zero\-downtime service restarts as the sockets buffer
+client requests until the service is able to handle them. The service manager
+sets the LISTEN_FDS environment variable to the number of passed file
+descriptors.
+.RE
+.SH "FILES"
+.sp
+\fI@SYSCONFDIR@/chrony.conf\fP
+.SH "SEE ALSO"
+.sp
+\fBchronyc(1)\fP, \fBchrony.conf(5)\fP
+.SH "BUGS"
+.sp
+For instructions on how to report bugs, please visit
+.URL "https://chrony\-project.org/" "" "."
+.SH "AUTHORS"
+.sp
+chrony was written by Richard Curnow, Miroslav Lichvar, and others.
\ No newline at end of file