NAME

       vnl-sort - sorts an vnlog file, preserving the legend

SYNOPSIS

        $ cat a.vnl
        # a b
        AA 11
        bb 12
        CC 13
        dd 14
        dd 123

        Sort lexically by a:
        $ <a.vnl vnl-sort -k a
        # a b
        AA 11
        CC 13
        bb 12
        dd 123
        dd 14

        Sort lexically by a, ignoring case:
        $ <a.vnl vnl-sort -k a --ignore-case
        # a b
        AA 11
        bb 12
        CC 13
        dd 123
        dd 14

        Sort lexically by a, then numerically by b:
        $ <a.vnl vnl-sort -k a -k b.n
        # a b
        AA 11
        CC 13
        bb 12
        dd 14
        dd 123

        Sort lexically by a, then numerically by b in reverse:
        $ <a.vnl vnl-sort -k a -k b.nr
        # a b
        AA 11
        CC 13
        bb 12
        dd 123
        dd 14

        Sort by month and then day:
        $ cat dat.vnl
        # month day
        March 5
        Jan 2
        Feb 1
        March 30
        Jan 21

        $ <dat.vnl vnl-sort -k month.M -k day.n
        # month day
        Jan 2
        Jan 21
        Feb 1
        March 5
        March 30

DESCRIPTION

         Usage: vnl-sort [options] logfile logfile logfile ... < logfile

       This tool sorts given vnlog files in various ways. "vnl-sort" is a wrapper around the GNU
       coreutils "sort" tool. Since this is a wrapper, most commandline options and behaviors of
       the "sort" tool are present; consult the sort(1) manpage for detail. The differences from
       GNU coreutils "sort" are

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

       •   The columns are referenced by name, not index. So instead of saying

             sort -k1

           to sort by the first column, you say

             sort -k time

           to sort by column "time".

       •   The fancy "KEYDEF" spec from "sort" is only partially supported. I only allow us to
           sort by full fields, so the start/stop positions don't make sense. I do support the
           "OPTS" to change the type of sorting in a given particular column. For instance, to
           sort by month and then by day, do this (see example above):

             vnl-sort -k month.M -k day.n

       •   "--files0-from" is not supported due to lack of time. If somebody really needs it,
           talk to me.

       •   "--output" is not supported due to an uninteresting technical limitation. The output
           always goes to standard out.

       •   "--field-separator" is not supported because vnlog assumes whitespace-separated fields

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

       •   By default we call the "sort" 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 "sort" does is supported, so see that man page for detailed
       documentation. Note that all non-legend comments are stripped out, since it's not obvious
       where they should end up.

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

       sort(1)

REPOSITORY

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

AUTHOR

       Dima Kogan "<dima@secretsauce.net>"

LICENSE AND COPYRIGHT

       Copyright 2018 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.

                                            2023-07-31                                VNL-SORT(1)