DOKK / manpages / debian 11 / vnlog / vnl-sort.1.en
VNL-SORT(1) vnlog VNL-SORT(1)

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

 $ 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


  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.

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.

sort(1)

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

Dima Kogan "<dima@secretsauce.net>"

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.

2020-12-09