centos man page for hwstamp_ctl

HWSTAMP_CTL(8)						      System Manager's Manual						    HWSTAMP_CTL(8)

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 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  pack-
       ets is not supported, the driver may time stamp more than just the requested types of packets.

       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							   November 2012						    HWSTAMP_CTL(8)