- Do not use mmap() by default; it can be enabled by --mmap - Add some minor optimizations for -u - Update manual page according to the changes Submitted by: Oleg Moskalenko <oleg.moskalenko@citrix.com>
639 lines
18 KiB
Groff
639 lines
18 KiB
Groff
.\" $OpenBSD: sort.1,v 1.31 2007/08/21 21:22:37 millert Exp $
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.\" $FreeBSD$
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.\"
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.\" Copyright (c) 1991, 1993
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.\" The Regents of the University of California. All rights reserved.
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.\"
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.\" This code is derived from software contributed to Berkeley by
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.\" the Institute of Electrical and Electronics Engineers, Inc.
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.\"
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.\" Redistribution and use in source and binary forms, with or without
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.\" modification, are permitted provided that the following conditions
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.\" are met:
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.\" 1. Redistributions of source code must retain the above copyright
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.\" notice, this list of conditions and the following disclaimer.
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.\" 2. Redistributions in binary form must reproduce the above copyright
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.\" notice, this list of conditions and the following disclaimer in the
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.\" documentation and/or other materials provided with the distribution.
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.\" 3. Neither the name of the University nor the names of its contributors
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.\" may be used to endorse or promote products derived from this software
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.\" without specific prior written permission.
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.\"
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.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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.\" SUCH DAMAGE.
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.\"
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.\" @(#)sort.1 8.1 (Berkeley) 6/6/93
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.\"
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.Dd May 25, 2012
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.Dt SORT 1
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.Os
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.Sh NAME
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.Nm sort
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.Nd sort or merge records (lines) of text and binary files
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.Sh SYNOPSIS
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.Nm sort
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.Bk -words
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.Op Fl bcCdfghiRMmnrsuVz
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.Sm off
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.Op Fl k\ \& Ar field1 Op , Ar field2
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.Sm on
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.Op Fl S Ar memsize
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.Ek
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.Op Fl T Ar dir
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.Op Fl t Ar char
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.Op Fl o Ar output
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.Op Ar file ...
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.Nm sort
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.Fl Fl help
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.Nm sort
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.Fl Fl version
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.Sh DESCRIPTION
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The
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.Nm
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utility sorts text and binary files by lines.
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A line is a record separated from the subsequent record by a
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newline (default) or NUL \'\\0\' character (-z option).
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A record can contain any printable or unprintable characters.
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Comparisons are based on one or more sort keys extracted from
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each line of input, and are performed lexicographically,
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according to the current locale's collating rules and the
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specified command-line options that can tune the actual
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sorting behavior.
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By default, if keys are not given,
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.Nm
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uses entire lines for comparison.
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.Pp
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The command line options are as follows:
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.Bl -tag -width Ds
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.It Fl c, Fl Fl check, Fl C, Fl Fl check=silent|quiet
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Check that the single input file is sorted.
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If the file is not sorted,
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.Nm
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produces the appropriate error messages and exits with code 1,
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otherwise returns 0.
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If
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.Fl C
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or
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.Fl Fl check=silent
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is specified,
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.Nm
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produces no output.
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This is a "silent" version of
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.Fl c.
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.It Fl m , Fl Fl merge
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Merge only.
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The input files are assumed to be pre-sorted.
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If they are not sorted the output order is undefined.
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.It Fl o Ar output , Fl Fl output Ns = Ns Ar output
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|
Print the output to the
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.Ar output
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file instead of the standard output.
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.It Fl S Ar size, Fl Fl buffer-size Ns = Ns Ar size
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Use
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.Ar size
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for the maximum size of the memory buffer.
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Size modifiers %,b,K,M,G,T,P,E,Z,Y can be used.
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If a memory limit is not explicitly specified,
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.Nm
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takes up to about 90% of available memory.
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If the file size is too big to fit into the memory buffer,
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the temporary disk files are used to perform the sorting.
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.It Fl T Ar dir , Fl Fl temporary-directory Ns = Ns Ar dir
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Store temporary files in the directory
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.Ar dir .
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The default path is the value of the environment variable
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.Ev TMPDIR
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or
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.Pa /var/tmp
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if
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.Ev TMPDIR
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is not defined.
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.It Fl u , Fl Fl unique
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Unique keys.
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Suppress all lines that have a key that is equal to an already
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processed one.
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This option, similarly to
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.Fl s ,
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implies a stable sort.
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If used with
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.Fl c
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or
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.Fl C ,
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.Nm
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also checks that there are no lines with duplicate keys.
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.It Fl s
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Stable sort.
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This option maintains the original record order of records that have
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and equal key.
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This is a non-standard feature, but it is widely accepted and used.
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.It Fl Fl version
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Print the version and silently exits.
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.It Fl Fl help
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Print the help text and silently exits.
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.El
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.Pp
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The following options override the default ordering rules.
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When ordering options appear independently of key field
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specifications, they apply globally to all sort keys.
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When attached to a specific key (see
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.Fl k ) ,
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the ordering options override all global ordering options for
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the key they are attahced to.
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.Bl -tag -width indent
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.It Fl b, Fl Fl ignore-leading-blanks
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Ignore leading blank characters when comparing lines.
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.It Fl d , Fl Fl dictionary-order
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Consider only blank spaces and alphanumeric characters in comparisons.
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.It Fl f , Fl Fl ignore-case
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Convert all lowercase characters to their uppercase equivalent
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before comparison, that is, perform case-independent sorting.
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.It Fl g, Fl Fl general-numeric-sort, Fl Fl sort=general-numeric
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Sort by general numerical value.
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As opposed to
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.Fl n ,
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this option handles general floating points, which have a much
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permissive format than those allowed by
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. Fl n ,
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but it has a significant performance drawback.
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.It Fl h, Fl Fl human-numeric-sort, Fl Fl sort=human-numeric
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Sort by numerical value, but take into account the SI suffix,
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if present.
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Sort first by numeric sign (negative, zero, or
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positive); then by SI suffix (either empty, or `k' or `K', or one
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of `MGTPEZY', in that order); and finally by numeric value.
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The SI suffix must immediately follow the number.
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For example, '12345K' sorts before '1M', because M is "larger" than K.
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This sort option is useful for sorting the output of a single invocation
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of 'df' command with
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.Fl h
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or
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.Fl H
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options (human-readable).
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.It Fl i , Fl Fl ignore-nonprinting
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Ignore all non-printable characters.
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.It Fl M, Fl Fl month-sort, Fl Fl sort=month
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Sort by month abbreviations.
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Unknown strings are considered smaller than the month names.
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.It Fl n , Fl Fl numeric-sort, Fl Fl sort=numeric
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Sort fields numerically by arithmetic value.
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Fields are supposed to have optional blanks in the beginning, an
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optional minus sign, zero or more digits (including decimal point and
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possible thousand separators).
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.It Fl R, Fl Fl random-sort, Fl Fl sort=random
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Sort by a random order.
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This is a random permutation of the inputs except that
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the equal keys sort together.
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It is implemented by hashing the input keys and sorting
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the hash values.
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The hash function is choosen randomly.
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The hash function is randomized by
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.Cm /dev/random
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content, or by file content if it is specified by
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.Fl Fl random-source .
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Even if multiple sort fields are specified,
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the same random hash function is used for all of them.
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.It Fl r , Fl Fl reverse
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Sort in reverse order.
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.It Fl V, Fl Fl version-sort
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Sort version numbers.
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The input lines are treated as file names in form
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PREFIX VERSION SUFFIX, where SUFFIX matches the regular expression
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"(\.([A-Za-z~][A-Za-z0-9~]*)?)*".
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The files are compared by their prefixes and versions (leading
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zeros are ignored in version numbers, see example below).
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If an input string does not match the pattern, then it is compared
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using the byte compare function.
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All string comparisions are performed in C locale, the locale
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environment setting is ignored.
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.Bl -tag -width indent
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.It Example:
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.It $ ls sort* | sort -V
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.It sort-1.022.tgz
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.It sort-1.23.tgz
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.It sort-1.23.1.tgz
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.It sort-1.024.tgz
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.It sort-1.024.003.
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.It sort-1.024.003.tgz
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.It sort-1.024.07.tgz
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.It sort-1.024.009.tgz
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.El
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.El
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.Pp
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The treatment of field separators can be altered using these options:
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.Bl -tag -width indent
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.It Fl b , Fl Fl ignore-leading-blanks
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Ignore leading blank space when determining the start
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and end of a restricted sort key (see
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.Fl k
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).
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If
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.Fl b
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is specified before the first
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.Fl k
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option, it applies globally to all key specifications.
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Otherwise,
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.Fl b
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can be attached independently to each
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.Ar field
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argument of the key specifications.
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.Fl b .
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.It Xo
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.Sm off
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.Fl k\ \& Ar field1 Op , Ar field2 , Fl Fl key Ns = Ns Ar field1 Op , Ar field2
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.Sm on
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.Xc
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|
Define a restricted sort key that has the starting position
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.Ar field1 ,
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and optional ending position
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.Ar field2
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of a key field.
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The
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.Fl k
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option may be specified multiple times,
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in which case subsequent keys are compared when earlier keys compare equal.
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The
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.Fl k
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option replaces the obsolete options
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.Cm \(pl Ns Ar pos1
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and
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.Fl Ns Ar pos2 ,
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but the old notation is also supported.
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.It Fl t Ar char , Fl Fl field-separator Ns = Ns Ar char
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Use
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.Ar char
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as a field separator character.
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The initial
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.Ar char
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is not considered to be part of a field when determining key offsets.
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Each occurrence of
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.Ar char
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is significant (for example,
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.Dq Ar charchar
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delimits an empty field).
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If
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.Fl t
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is not specified, the default field separator is a sequence of
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blank space characters, and consecutive blank spaces do
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.Em not
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delimit an empty field, however, the initial blank space
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.Em is
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considered part of a field when determining key offsets.
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To use NUL as field separator, use
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.Fl t
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\'\\0\'.
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.It Fl z , Fl Fl zero-terminated
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Use NUL as record separator.
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By default, records in the files are supposed to be separated by
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the newline characters.
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With this option, NUL (\'\\0\') is used as a record separator character.
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.El
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.Pp
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Other options:
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.Bl -tag -width indent
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.It Fl Fl batch-size Ns = Ns Ar num
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Specify maximum number of files that can be opened by
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.Nm
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at once.
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This option affects behavior when having many input files or using
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temporary files.
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The default value is 16.
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.It Fl Fl compress-program Ns = Ns Ar PROGRAM
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Use PROGRAM to compress temporary files.
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PROGRAM must compress standard input to standard output, when called
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without arguments.
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When called with argument
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.Fl d
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it must decompress standard input to standard output.
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If PROGRAM fails,
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.Nm
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must exit with error.
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An example of PROGRAM that can be used here is bzip2.
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.It Fl Fl random-source Ns = Ns Ar filename
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In random sort, the file content is used as the source of the 'seed' data
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for the hash function choice.
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Two invocations of random sort with the same seed data will use
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the same hash function and will produce the same result if the input is
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also identical.
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By default, file
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.Cm /dev/random
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is used.
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.It Fl Fl debug
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Print some extra information about the sorting process to the
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standard output.
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%%THREADS%%.It Fl Fl nthreads
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%%THREADS%%Set the maximum number of execution threads.
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%%THREADS%%Default number equals to the number of CPUs.
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.It Fl Fl files0-from Ns = Ns Ar filename
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Take the input file list from the file
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.Ar filename.
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The file names must be separated by NUL
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(like the output produced by the command "find ... -print0").
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.It Fl Fl radixsort
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Try to use radix sort, if the sort specifications allow.
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The radix sort can only be used for trivial locales (C and POSIX),
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and it cannot be used for numeric or month sort.
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Radix sort is very fast and stable.
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.It Fl Fl mergesort
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Use mergesort.
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This is a universal algorithm that can always be used,
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but it is not always the fastest.
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.It Fl Fl qsort
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Try to use quick sort, if the sort specifications allow.
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This sort algorithm cannot be used with
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.Fl u
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and
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.Fl s .
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.It Fl Fl heapsort
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|
Try to use heap sort, if the sort specifications allow.
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This sort algorithm cannot be used with
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.Fl u
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and
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.Fl s .
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.It Fl Fl mmap
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Try to use file memory mapping system call.
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It may increase speed in some cases.
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.El
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.Pp
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The following operands are available:
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.Bl -tag -width indent
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.It Ar file
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The pathname of a file to be sorted, merged, or checked.
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If no
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.Ar file
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operands are specified, or if a
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.Ar file
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operand is
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.Fl ,
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the standard input is used.
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.El
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.Pp
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A field is defined as a maximal sequence of characters other than the
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field separator and record separator (newline by default).
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Initial blank spaces are included in the field unless
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.Fl b
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has been specified;
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the first blank space of a sequence of blank spaces acts as the field
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separator and is included in the field (unless
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.Fl t
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is specified).
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For example, all blank spaces at the beginning of a line are
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considered to be part of the first field.
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.Pp
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Fields are specified by the
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.Sm off
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.Fl k\ \& Ar field1 Op , Ar field2
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.Sm on
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command-line option.
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If
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.Ar field2
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is missing, the end of the key defaults to the end of the line.
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.Pp
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The arguments
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.Ar field1
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and
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.Ar field2
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have the form
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.Em m.n
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.Em (m,n > 0)
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and can be followed by one or more of the modifiers
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.Cm b , d , f , i ,
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.Cm n , g , M
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and
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.Cm r ,
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which correspond to the options discussed above.
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When
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.Cm b
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is specified it applies only to
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.Ar field1
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or
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.Ar field2
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where it is specified while the rest of the modifiers
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apply to the whole key field regardless if they are
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specified only with
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.Ar field1
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or
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.Ar field2
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or both.
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A
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.Ar field1
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position specified by
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.Em m.n
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|
is interpreted as the
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.Em n Ns th
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|
character from the beginning of the
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.Em m Ns th
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|
field.
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|
A missing
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.Em \&.n
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in
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.Ar field1
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means
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|
.Ql \&.1 ,
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indicating the first character of the
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.Em m Ns th
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field; if the
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.Fl b
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option is in effect,
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.Em n
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|
is counted from the first non-blank character in the
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.Em m Ns th
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|
field;
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|
.Em m Ns \&.1b
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|
refers to the first non-blank character in the
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.Em m Ns th
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|
field.
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|
.No 1\&. Ns Em n
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|
refers to the
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.Em n Ns th
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|
character from the beginning of the line;
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|
if
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.Em n
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|
is greater than the length of the line, the field is taken to be empty.
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.Pp
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|
.Em n Ns th
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positions are always counted from the field beginning, even if the field
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is shorter than the number of specified positions.
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|
Thus, the key can really start from a position in a subsequent field.
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.Pp
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|
A
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.Ar field2
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|
position specified by
|
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.Em m.n
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|
is interpreted as the
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|
.Em n Ns th
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|
character (including separators) from the beginning of the
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.Em m Ns th
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|
field.
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|
A missing
|
|
.Em \&.n
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|
indicates the last character of the
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|
.Em m Ns th
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|
field;
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|
.Em m
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|
= \&0
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|
designates the end of a line.
|
|
Thus the option
|
|
.Fl k Ar v.x,w.y
|
|
is synonymous with the obsolete option
|
|
.Cm \(pl Ns Ar v-\&1.x-\&1
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|
.Fl Ns Ar w-\&1.y ;
|
|
when
|
|
.Em y
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|
is omitted,
|
|
.Fl k Ar v.x,w
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|
is synonymous with
|
|
.Cm \(pl Ns Ar v-\&1.x-\&1
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|
.Fl Ns Ar w\&.0 .
|
|
The obsolete
|
|
.Cm \(pl Ns Ar pos1
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|
.Fl Ns Ar pos2
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|
option is still supported, except for
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|
.Fl Ns Ar w\&.0b ,
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|
which has no
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|
.Fl k
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|
equivalent.
|
|
.Sh EXIT STATUS
|
|
The
|
|
.Nm
|
|
utility shall exit with one of the following values:
|
|
.Pp
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|
.Bl -tag -width flag -compact
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|
.It 0
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|
Successfully sorted the input files or if used with
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|
.Fl c
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|
or
|
|
.Fl C ,
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|
the input file already met the sorting criteria.
|
|
.It 1
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|
On disorder (or non-uniqueness) with the
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|
.Fl c
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|
or
|
|
.Fl C
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|
options.
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|
.It 2
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|
An error occurred.
|
|
.El
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|
.Sh ENVIRONMENT
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|
.Bl -tag -width Fl
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|
.It Ev LC_COLLATE
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|
Locale settings to be used to determine the collation for
|
|
sorting records.
|
|
.It Ev LC_CTYPE
|
|
Locale settings to be used to case conversion and classification
|
|
of characters, that is, which characters are considered
|
|
whitespaces, etc.
|
|
.It Ev LC_MESSAGES
|
|
Locale settings that determine the language of output messages
|
|
that
|
|
.Nm
|
|
prints out.
|
|
.It Ev LC_NUMERIC
|
|
Locale settings that determine the number format used in numeric sort.
|
|
.It Ev LC_TIME
|
|
Locale settings that determine the month format used in month sort.
|
|
.It Ev LC_ALL
|
|
Locale settings that override all of the above locale settings.
|
|
This environment variable can be used to set all these settings
|
|
to the same value at once.
|
|
.It Ev LANG
|
|
Used as a last resort to determine different kinds of locale-specific
|
|
behavior if neither the respective environment variable, nor
|
|
.Ev LC_ALL
|
|
are set.
|
|
%%NLS%%.It Ev NLSPATH
|
|
%%NLS%%Path to NLS catalogs.
|
|
.It Ev TMPDIR
|
|
Path to the directory in which temporary files will be stored.
|
|
Note that
|
|
.Ev TMPDIR
|
|
may be overridden by the
|
|
.Fl T
|
|
option.
|
|
.It Ev GNUSORT_NUMERIC_COMPATIBILITY
|
|
If defined
|
|
.Fl t
|
|
will not override the locale numeric symbols, that is, thousand
|
|
separators and decimal separators.
|
|
By default, if we specify
|
|
.Fl t
|
|
with the same symbol as the thousand separator or decimal point,
|
|
the symbol will be treated as the field separator.
|
|
Older behavior was less definite; the symbol was treated as both field
|
|
separator and numeric separator, simultaneously.
|
|
This environment variable enables the old behavior.
|
|
.El
|
|
.Sh FILES
|
|
.Bl -tag -width Pa -compact
|
|
.It Pa /var/tmp/.bsdsort.PID.*
|
|
Temporary files.
|
|
.It Pa /dev/random
|
|
Default seed file for the random sort.
|
|
.El
|
|
.Sh SEE ALSO
|
|
.Xr comm 1 ,
|
|
.Xr join 1 ,
|
|
.Xr uniq 1 .
|
|
.Sh STANDARDS
|
|
The
|
|
.Nm
|
|
utility is compliant with the
|
|
.St -p1003.1-2008
|
|
specification.
|
|
.Pp
|
|
The flags
|
|
.Op Fl ghRMSsTVz
|
|
are extensions to the POSIX specification.
|
|
.Pp
|
|
All long options are extensions to the specification, some of them are
|
|
provided for compatibility with GNU versions and some of them are
|
|
own extensions.
|
|
.Pp
|
|
The old key notations
|
|
.Cm \(pl Ns Ar pos1
|
|
and
|
|
.Fl Ns Ar pos2
|
|
come from older versions of
|
|
.Nm
|
|
and are still supported but their use is highly discouraged.
|
|
.Sh HISTORY
|
|
A
|
|
.Nm
|
|
command first appeared in
|
|
.At v3 .
|
|
.Sh AUTHORS
|
|
Gabor Kovesdan <gabor@FreeBSD.org>,
|
|
.Pp
|
|
Oleg Moskalenko <oleg.moskalenko@citrix.com>
|
|
.Sh NOTES
|
|
This implementation of
|
|
.Nm
|
|
has no limits on input line length (other than imposed by available
|
|
memory) or any restrictions on bytes allowed within lines.
|
|
.Pp
|
|
The performance depends highly on locale settings,
|
|
efficient choice of sort keys and key complexity.
|
|
The fastest sort is with locale C, on whole lines,
|
|
with option
|
|
.Fl s.
|
|
In general, locale C is the fastest, then single-byte
|
|
locales follow and multi-byte locales as the slowest but
|
|
the correct collation order is always respected.
|
|
As for the key specification, the simpler to process the
|
|
lines the faster the search will be.
|
|
.Pp
|
|
When sorting by arithmetic value, using
|
|
.Fl n
|
|
results in much better performance than
|
|
.Fl g
|
|
so its use is encouraged
|
|
whenever possible.
|