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 evertyhing 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.