NAME

       hwstamp_ctl - set time stamping policy at the driver level

SYNOPSIS

       hwstamp_ctl -i interface [ -r rx-filter ] [ -t tx-type ] [ -v ]

DESCRIPTION

       hwstamp_ctl  is  a  program  used  to set and get the hardware time stamping policy at the network driver
       level with the SIOCSHWTSTAMP ioctl(2).  The tx-type and rx-filter values are hints to the driver what  it
       is  expected  to  do.  If the requested fine-grained filtering for incoming packets is not supported, the
       driver may time stamp more than just the requested types of packets.

       If neither tx-type nor rx-filter values are passed to the program, it will use the SIOCGHWTSTAMP ioctl(2)
       to non-destructively read the current hardware time stamping policy.

       This program is a debugging tool. The ptp4l(8) program does not need this program to  function,  it  will
       set the policy automatically as appropriate.

OPTIONS

       -i interface
              Specify the network interface of which the policy should be changed.

       -r rx-filter
              Specify which types of incoming packets should be time stamped, rx-filter is an integer value.

       -t tx-type
              Enable or disable hardware time stamping for outgoing packets, tx-type is an integer value.

       -h     Display a help message and list of possible values for rx-filter and tx-type.

       -v     Prints the software version and exits.

SEE ALSO

       ioctl(2), ptp4l(8)

linuxptp                                            June 2014                                     HWSTAMP_CTL(8)