NAME

       snooper — a utility for capturing data flowing between serial devices

SYNOPSIS

       snooper [-h]
       snooper [-b baudrate] [-t] [-u] [-x] [-n] port0 port1

DESCRIPTION

       snooper passes data transparently between two serial (RS232C) devices, capturing and logging the data and
       occasional comments you want to insert into the logs.

       It  is  useful  for  debugging  or  analyzing  the communications protocol between two devices that would
       normally be connected directly to each other, e.g. a digital camera and a personal computer.  By  sitting
       in  the  middle (after you connect the two devices to serial ports on your Linux machine) snooper is able
       to capture data traveling in either direction while also passing it unmodified to the other device.

       It is also possible to operate with a single serial device, using your console and keyboard as the second
       device.

OPTIONS

       -b baudrate
               Specify baudrate to use.  Default baudrate is 9600.

       -t      Include current time (in microseconds) with each write to the textual  log  file.   See  L  under
               KEYBOARD COMMANDS, below.

       -u      Do not perform serial device locking.  (This option is discouraged, and should never be necessary
               on a properly-configured Debian system.)

       -x      Hex display only.  (Even printable characters will be displayed in hex.)

       -n      Do not forward traffic between the two ports; useful when you have a splitter cable.

       -h      Help; presents a brief synopsis of the command line options.

KEYBOARD COMMANDS

       snooper has a set of commands that act similar to those of vi.

       Note  that  the  characters  transmitted  into the serial ports will not be forwarded while snooper is in
       command parameter input mode.  You should therefore set the log file and so forth while the  serial  line
       has no activity.

       L       Switch textual log file.  You'll be asked to answer the filename of the log file.

       B       Switch  binary  log  file.   You'll  asked  to answer which device to log, and the log file name.
               Please note that the binary  log  will  contain  the  input  from  the  perspective  of  snooper.
               Therefore,  if  you  would  like  to  make  a log of input of line 0 (thus the output from device
               connected to line 0), you shold specify line 0.  You should use a file that is  local,  or  on  a
               virtual disk, so that no characters will be lost.

       m       add  a  memo  line to the text log file.  The memo line will contain a timestamp and the text you
               provide.

       Q       Quit.

       c       Reset the counter.

       b       Change the baudrate.

       C       Make the console act as one of the serial lines.  ESC Go back to command mode.  ^V Quote the next
               char (so that you can send ESC, for example).  ^X input a byte  by  its  2-character  hexadecimal
               value  (so  that  you can send any character you like).  By tapping any other key, that character
               will be sent to the line.

       ^L      Repaint the screen.
       An unrecognized command character will present a brief list of the valid command characters.

EXAMPLE

             snooper /dev/ttyS0 /dev/ttyS1

AUTHOR

       Jun-ichiro Itoh <itojun@itojun.org>

       This man page was written by David Coe <davidc@debian.org> for the Debian project, and  may  be  used  by
       others under the terms of the GNU General Purpose License, version 2 or later.

Debian                                          Januray 20, 2002                                      SNOOPER(1)