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USBDUMP(8)              FreeBSD System Manager's Manual             USBDUMP(8)

     usbdump - dump traffic on USB host controller

     usbdump [-i ifname] [-r file] [-s snaplen] [-v] [-w file] [-f filter]
             [-b file] [-h]

     The usbdump utility provides a way to dump USB packets on host

     The following options are accepted:

     -b file        Store data part of the USB trace in binary format to the
                    given file.  This option also works with the -r and -f

     -i ifname      Listen on USB bus interface ifname.

     -r file        Read the raw packets from file.  This option also works
                    with the -f option.

     -s snaplen     Snapshot snaplen bytes from each packet.

     -v             Enable debugging messages.  When defined multiple times
                    the verbosity level increases.

     -w file        Write the raw packets to file.  This option also works
                    with the -s and -v options.

     -f filter      The filter argument consists of either one or two numbers
                    separated by a dot.  The first indicates the device unit
                    number which should be traced.  The second number which is
                    optional indicates the endpoint which should be traced.
                    To get all traffic for the control endpoint, two filters
                    should be created, one for endpoint 0 and one for endpoint
                    128.  If 128 is added to the endpoint number that means IN
                    direction, else OUT direction is implied.  A device unit
                    or endpoint value of -1 means ignore this field.  If no
                    filters are specified, all packets are passed through
                    using the default -1,-1 filter.  This option can be
                    specified multiple times.

     -h             This option displays a summary of the command line

     Capture the USB raw packets on usbus2:

           usbdump -i usbus2 -s 256 -v

     Dump the USB raw packets of usbus2 into the file without packet size

           usbdump -i usbus2 -s 0 -w /tmp/dump_pkts

     Dump the USB raw packets of usbus2, but only the control endpoint traffic
     of device unit number 3:

           usbdump -i usbus2 -s 0 -f 3.0 -f 3.128 -w /tmp/dump_pkts

     Read and display the USB raw packets from previous file:

           usbdump -r /tmp/dump_pkts -v

     The output format of usbdump is as follows:

           <time> <bus>.<addr> <ep> <xfertype> <S/D> (<frames>/<length>) <...>

     The meaning of the output format elements is as follows:

     <time>      A timestamp preceding all output lines.  The timestamp has
                 the format "hh:mm:ss.frac" and is as accurate as the kernel's

     <bus>       The USB host controller's bus unit number.

     <addr>      The unique number of the USB device as allocated by the host
                 controller driver.

     <ep>        The USB endpoint address that indicates whether the address
                 is OUT or IN.

     <xfertype>  The USB transfer type.  Can be CTRL, ISOC, BULK or INTR.

     <S/D>       `S' indicates a USB submit.  `D' indicates a USB transfer

     <frames>    Numbers of frames in this packets.  If this is a USB submit,
                 its value is xfer->nframes which means how many frames are
                 acceptable or registered to transfer.  If this is a USB done,
                 xfer->aframes is the actual number of frames.

     <length>    Total packet size.  If this is a USB submit, its value is
                 xfer->sumlen.  If this is a USB done, its value is

     <...>       Optional field used for printing an error string if the
                 packet is from USB done.


     Weongyo Jeong <>

FreeBSD 11.0-PRERELEASE         April 24, 2012         FreeBSD 11.0-PRERELEASE


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