# lsclocks

## NAME



           lsclocks - display system clocks
    


## SYNOPSIS



           **lsclocks**[option]
    


## DESCRIPTION



           **lsclocks** is a simple command to display system clocks.
    
           It allows to display information like current time and resolution
           of clocks. Different kinds of clocks are supported.
    
           •   POSIX clocks: **CLOCK_MONOTONIC** , **CLOCK_REALTIME** , **CLOCK_BOOTTIME** ,
               etc.
    
           •   CPU clocks: **clock_getcpuclockid()**.
    
           •   PTP clocks: **/dev/ptp0**.
    
           •   RTC clocks: **/dev/rtc0**.
    


## OPTIONS



           **-J** , **--json**
               Use JSON output format.
    
           **-n** , **--noheadings**
               Don’t print headings.
    
           **-o** , **--output** _list_
               Specify which output columns to print. See the **OUTPUT COLUMNS**
               section for details of available columns.
    
           **--output-all**
               Output all columns.
    
           **-r** , **--raw**
               Use raw output format.
    
           **-t** , **--time** _clock_
               Show current time of one specific clock.
    
           **--no-discover-dynamic**
               Do not try to discover dynamic clocks.
    
           **-d** , **--dynamic-clock** _path_
               Also display specified dynamic clock. Can be specified
               multiple times.
    
           **--no-discover-rtc**
               Do not try to discover RTCs.
    
           **-x** , **--rtc** _path_
               Also display specified RTC. Can be specified multiple times.
    
           **-c** , **--cpu-clock** _pid_
               Also display CPU clock of specified process. Can be specified
               multiple times.
    
           **-h** , **--help**
               Display help text and exit.
    
           **-V** , **--version**
               Display version and exit.
    


## OUTPUT COLUMNS



           Each column has a type. Types are surround by < and >.
    
           TYPE <string>
               Clock type.
    
           ID <number>
               Numeric clock ID.
    
           CLOCK <string>
               Name in the form **CLOCK_**
    
           NAME <string>
               Shorter, easier to read name.
    
           TIME <number>
               Current clock timestamp as returned by **clock_gettime()**.
    
           ISO_TIME <string>
               ISO8601 formatted version of **TIME**.
    
           RESOL_RAW <number>
               Clock resolution as returned by clock_getres(2).
    
           RESOL <number>
               Human readable version of **RESOL_RAW**.
    
           REL_TIME <string>
               **TIME** time formatted as time range.
    
           NS_OFFSET <number>
               Offset of the current namespace to the parent namespace as
               read from **/proc/self/timens_offsets**.
    


## AVAILABILITY



           The **lsclocks** command is part of the util-linux package which can
           be downloaded from Linux Kernel Archive
           <https://www.kernel.org/pub/linux/utils/util-linux/>. This page is
           part of the _util-linux_ (a random collection of Linux utilities)
           project. Information about the project can be found at 
           ⟨https://www.kernel.org/pub/linux/utils/util-linux/⟩. If you have a
           bug report for this manual page, send it to
           util-linux@vger.kernel.org. This page was obtained from the
           project's upstream Git repository
           ⟨git://git.kernel.org/pub/scm/utils/util-linux/util-linux.git⟩ on
           2025-08-11. (At that time, the date of the most recent commit that
           was found in the repository was 2025-08-05.) If you discover any
           rendering problems in this HTML version of the page, or you
           believe there is a better or more up-to-date source for the page,
           or you have corrections or improvements to the information in this
           COLOPHON (which is _not_ part of the original manual page), send a
           mail to man-pages@man7.org
    
    util-linux 2.42-start-521-ec46  2025-08-09                    _LSCLOCKS_(1)
    


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