NAME

       lcm-logger - data logger

SYNOPSIS

       lcm-logger [options] [FILE]

DESCRIPTION

       LCM  message  logging  utility.   Subscribes  to all channels on an LCM network, and records all messages
       received to FILE.  If FILE is not specified, then a filename is automatically chosen.

OPTIONS

       The following options are provided by lcm-logger

       -c, --channel=CHAN
              Channel string to pass to lcm_subscribe. (default: ".*")

       --flush-interval=MS
              Flush the log file to disk every MS milliseconds. (default: 100)

       -f, --force
              Overwrite existing files.  The default behavior is to fail if the output file already exists.

       -h, --help
              Shows some help text and exits

       -i, --increment
              Automatically append a suffix to FILE such that the resulting filename  does  not  already  exist.
              This option precludes -f and --rotate.

       -l, --lcm-url=URL
              Log messages on the specified LCM URL

       -m, --max-unwritten-mb=SIZE
              Maximum  size  of  received  but  unwritten  messages to store in memory before dropping messages.
              (default: 100 MB)

       --rotate=NUM
              When creating a new log file, rename existing files out of the way and always write to FILE.0.  If
              FILE.0 already exists, it is renamed to FILE.1.  If FILE.1 exists, it is renamed to  FILE.2,  etc.
              If FILE.NUM exists, then it is deleted.  This option precludes -i.

       --split-mb=N
              Automatically  start  writing  to  a  new  log file once the log file exceeds N MB in size (can be
              fractional).  This option requires -i or --rotate.

       -q, --quiet
              Suppress normal output and only report errors.

       -s, --strftime
              Format FILE with strftime.

       -v, --invert-channels
              Invert channels.  Log everything that CHAN does not match.

ROTATING AND SPLITTING

       For long-term logging, lcm-logger can rotate through a fixed number of log files, moving  to  a  new  log
       file as existing files reach a maximum size.  To do this, use --rotate and --split-mb.  For example:

           # Rotate through logfile.0, logfile.1, ... logfile.4
           lcm-logger --rotate=5 --split-mb=2 logfile

       Moving  to  a  new  file  happens  either  when  the current log file size exceeds the limit specified by
       --split-mb, or when lcm-logger receives a SIGHUP.

SIGNALS

       On platforms defining SIGHUP, lcm-logger will react to HUP by closing the active log file and  opening  a
       new one.

SEE ALSO

       strftime(3)

COPYRIGHT

       lcm-logger  is  part  of  the  Lightweight  Communications  and Marshalling (LCM) project.  Permission is
       granted to copy, distribute and/or modify it under the terms of the GNU Lesser General Public License  as
       published  by  the  Free  Software Foundation; either version 2.1 of the License, or (at your option) any
       later version.  See the file COPYING in the LCM distribution for more details regarding distribution.

       LCM is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
       warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.   See  the  GNU  Lesser  General  Public
       License for more details.  You should have received a copy of the GNU Lesser General Public License along
       with  LCM;  if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
       MA 02110-1301 USA

AUTHOR

       This manual page was written by Albert Huang.

LCM                                                2009-07-28                                      lcm-logger(1)