NAME

       vnl-uniq - uniq a log file, preserving the legend

SYNOPSIS

        $ cat colors.vnl
        # color
        blue
        yellow
        yellow
        blue
        yellow
        orange
        orange

        $ < colors.vnl | vnl-sort | vnl-uniq -c
        # count color
              2 blue
              2 orange
              3 yellow

DESCRIPTION

         Usage: vnl-uniq [options] < logfile

       This tool runs "uniq" on a given vnlog dataset. "vnl-uniq" is a wrapper around the GNU
       coreutils "uniq" tool. Since this is a wrapper, most commandline options and behaviors of
       the "uniq" tool are present; consult the uniq(1) manpage for detail. The differences from
       GNU coreutils "uniq" are

       •   The input and output to this tool are vnlog files, complete with a legend

       •   "--zero-terminated" is not supported because vnlog assumes newline-separated records

       •   Only one input is supported (a file on the cmdline or data on standard input), and the
           output always goes to standard output. Specifying the output as a file on the
           commandline is not supported.

       •   "--vnl-count NAME" can be given to name the "count" column. "-c" is still supported to
           add the default new column named "count", but if another name is wanted, "--vnl-count"
           does that. "--vnl-count" implies "-c"

       •   In addition to the normal behavior of skipping fields at the start, "-f" and
           "--skip-fields" can take a negative argument to skip the all but the last N fields.
           For instance, to use only the one last field, pass "-f -1" or "--skip-fields=-1".

       •   By default we call the "uniq" tool to do the actual work. If the underlying tool has a
           different name or lives in an odd path, this can be specified by passing "--vnl-tool
           TOOL"

       Past that, everything "uniq" does is supported, so see that man page for detailed
       documentation.

COMPATIBILITY

       I use GNU/Linux-based systems exclusively, but everything has been tested functional on
       FreeBSD and OSX in addition to Debian, Ubuntu and CentOS. I can imagine there's something
       I missed when testing on non-Linux systems, so please let me know if you find any issues.

SEE ALSO

       uniq(1)

REPOSITORY

       https://github.com/dkogan/vnlog/

AUTHOR

       Dima Kogan "<dima@secretsauce.net>"

LICENSE AND COPYRIGHT

       Copyright 2019 Dima Kogan "<dima@secretsauce.net>"

       This library is free software; you can redistribute it 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.

                                            2022-06-28                                VNL-UNIQ(1)