Xfer

timestamping interface option*

Options:
  IP_MULTICAST_LOOP - looping outgoing multicasts
  SO_TIMESTAMP - normal software time stamping, ms resolution
  SO_TIMESTAMPNS - more accurate software time stamping
  SOF_TIMESTAMPING_TX_HARDWARE - hardware time stamping of outgoing packets
  SOF_TIMESTAMPING_TX_SOFTWARE - software fallback for outgoing packets
  SOF_TIMESTAMPING_RX_HARDWARE - hardware time stamping of incoming packets
  SOF_TIMESTAMPING_RX_SOFTWARE - software fallback for incoming packets
  SOF_TIMESTAMPING_SOFTWARE - request reporting of software time stamps
  SOF_TIMESTAMPING_RAW_HARDWARE - request reporting of raw HW time stamps
  SIOCGSTAMP - check last socket time stamp
  SIOCGSTAMPNS - more accurate socket time stamp

[jj5@cherry linux-ts]sudo ./a.out enp2s0f0 SOF_TIMESTAMPING_TX_HARDWARE SOF_TIMESTAMPING_RX_HARDWARE SOF_TIMESTAMPING_RAW_HARDWARE
SIOCSHWTSTAMP: tx_type 1 requested, got 1; rx_filter 4 requested, got 1
SO_TIMESTAMP 0
SO_TIMESTAMPNS 0
SO_TIMESTAMPING 69
1448770329.491771: select 508229us
1448770330.000542: select returned: 0, success
1448770330.000558: sent 124 bytes
1448770330.000559: select 4999441us
1448770330.000673: select returned: 1, success
ready for reading
recvmsg regular: Resource temporarily unavailable
1448770330.000686: received error data, 166 bytes from 69.0.0.152, 112 bytes control messages
   cmsg len 64: SOL_SOCKET SO_TIMESTAMPING SW 0.000000000 HW raw 431.339791492
   cmsg len 48: IPPROTO_IP IP_RECVERR ee_errno 'No message of desired type' ee_origin 4 => bounced packet => GOT OUR DATA BACK (HURRAY!)
1448770330.000696: select 4999304us
1448770335.005037: select returned: 0, success
1448770335.005047: sent 124 bytes 
1448770335.005048: select 4994952us
1448770335.005180: select returned: 1, success
ready for reading
recvmsg regular: Resource temporarily unavailable
1448770335.005200: received error data, 166 bytes from 69.0.0.152, 112 bytes control messages
   cmsg len 64: SOL_SOCKET SO_TIMESTAMPING SW 0.000000000 HW raw 436.344331004
   cmsg len 48: IPPROTO_IP IP_RECVERR ee_errno 'No message of desired type' ee_origin 4 => bounced packet => GOT OUR DATA BACK (HURRAY!)
1448770335.005215: select 4994785us
1448770340.005039: select returned: 0, success
1448770340.005049: sent 124 bytes
1448770340.005050: select 4994950us
1448770340.005155: select returned: 1, success
ready for reading
recvmsg regular: Resource temporarily unavailable
1448770340.005174: received error data, 166 bytes from 69.0.0.152, 112 bytes control messages
   cmsg len 64: SOL_SOCKET SO_TIMESTAMPING SW 0.000000000 HW raw 441.344329789
   cmsg len 48: IPPROTO_IP IP_RECVERR ee_errno 'No message of desired type' ee_origin 4 => bounced packet => GOT OUR DATA BACK (HURRAY!)
1448770340.005189: select 4994811us