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SORT(1)			FreeBSD	General	Commands Manual		       SORT(1)

     sort -- sort or merge records (lines) of text and binary files

     sort [-bcCdfghiRMmnrsuVz] [-k field1[,field2]] [-S	memsize] [-T dir]
	  [-t char] [-o	output]	[file ...]
     sort --help
     sort --version

     The sort utility sorts text and binary files by lines.  A line is a
     record separated from the subsequent record by a newline (default)	or NUL
     '\0' character (-z	option).  A record can contain any printable or	un-
     printable characters.  Comparisons	are based on one or more sort keys ex-
     tracted from each line of input, and are performed	lexicographically, ac-
     cording to	the current locale's collating rules and the specified com-
     mand-line options that can	tune the actual	sorting	behavior.  By default,
     if	keys are not given, sort uses entire lines for comparison.

     The command line options are as follows:

     -c, --check, -C, --check=silent|quiet
	     Check that	the single input file is sorted.  If the file is not
	     sorted, sort produces the appropriate error messages and exits
	     with code 1, otherwise returns 0.	If -C or --check=silent	is
	     specified,	sort produces no output.  This is a "silent" version
	     of	-c.

     -m, --merge
	     Merge only.  The input files are assumed to be pre-sorted.	 If
	     they are not sorted the output order is undefined.

     -o	output,	--output=output
	     Print the output to the output file instead of the	standard out-

     -S	size, --buffer-size=size
	     Use size for the maximum size of the memory buffer.  Size modi-
	     fiers %,b,K,M,G,T,P,E,Z,Y can be used.  If	a memory limit is not
	     explicitly	specified, sort	takes up to about 90% of available
	     memory.  If the file size is too big to fit into the memory buf-
	     fer, the temporary	disk files are used to perform the sorting.

     -T	dir, --temporary-directory=dir
	     Store temporary files in the directory dir.  The default path is
	     the value of the environment variable TMPDIR or /var/tmp if
	     TMPDIR is not defined.

     -u, --unique
	     Unique keys.  Suppress all	lines that have	a key that is equal to
	     an	already	processed one.	This option, similarly to -s, implies
	     a stable sort.  If	used with -c or	-C, sort also checks that
	     there are no lines	with duplicate keys.

     -s	     Stable sort.  This	option maintains the original record order of
	     records that have an equal	key.  This is a	non-standard feature,
	     but it is widely accepted and used.

	     Print the version and silently exits.

     --help  Print the help text and silently exits.

     The following options override the	default	ordering rules.	 When ordering
     options appear independently of key field specifications, they apply
     globally to all sort keys.	 When attached to a specific key (see -k), the
     ordering options override all global ordering options for the key they
     are attached to.

     -b, --ignore-leading-blanks
	     Ignore leading blank characters when comparing lines.

     -d, --dictionary-order
	     Consider only blank spaces	and alphanumeric characters in compar-

     -f, --ignore-case
	     Convert all lowercase characters to their uppercase equivalent
	     before comparison,	that is, perform case-independent sorting.

     -g, --general-numeric-sort, --sort=general-numeric
	     Sort by general numerical value.  As opposed to -n, this option
	     handles general floating points.  It has a	more permissive	format
	     than that allowed by -n but it has	a significant performance

     -h, --human-numeric-sort, --sort=human-numeric
	     Sort by numerical value, but take into account the	SI suffix, if
	     present.  Sort first by numeric sign (negative, zero, or posi-
	     tive); then by SI suffix (either empty, or	`k' or `K', or one of
	     `MGTPEZY',	in that	order);	and finally by numeric value.  The SI
	     suffix must immediately follow the	number.	 For example, '12345K'
	     sorts before '1M',	because	M is "larger" than K.  This sort op-
	     tion is useful for	sorting	the output of a	single invocation of
	     'df' command with -h or -H	options	(human-readable).

     -i, --ignore-nonprinting
	     Ignore all	non-printable characters.

     -M, --month-sort, --sort=month
	     Sort by month abbreviations.  Unknown strings are considered
	     smaller than the month names.

     -n, --numeric-sort, --sort=numeric
	     Sort fields numerically by	arithmetic value.  Fields are supposed
	     to	have optional blanks in	the beginning, an optional minus sign,
	     zero or more digits (including decimal point and possible thou-
	     sand separators).

     -R, --random-sort,	--sort=random
	     Sort by a random order.  This is a	random permutation of the in-
	     puts except that the equal	keys sort together.  It	is implemented
	     by	hashing	the input keys and sorting the hash values.  The hash
	     function is chosen	randomly.  The hash function is	randomized by
	     /dev/random content, or by	file content if	it is specified	by
	     --random-source.  Even if multiple	sort fields are	specified, the
	     same random hash function is used for all of them.

     -r, --reverse
	     Sort in reverse order.

     -V, --version-sort
	     Sort version numbers.  The	input lines are	treated	as file	names
	     in	form PREFIX VERSION SUFFIX, where SUFFIX matches the regular
	     expression	"(.([A-Za-z~][A-Za-z0-9~]*)?)*".  The files are	com-
	     pared by their prefixes and versions (leading zeros are ignored
	     in	version	numbers, see example below).  If an input string does
	     not match the pattern, then it is compared	using the byte compare
	     function.	All string comparisons are performed in	C locale, the
	     locale environment	setting	is ignored.


	     $ ls sort*	| sort -V









     The treatment of field separators can be altered using these options:

     -b, --ignore-leading-blanks
	     Ignore leading blank space	when determining the start and end of
	     a restricted sort key (see	-k).  If -b is specified before	the
	     first -k option, it applies globally to all key specifications.
	     Otherwise,	-b can be attached independently to each field argu-
	     ment of the key specifications.  -b.

     -k	field1[,field2], --key=field1[,field2]
	     Define a restricted sort key that has the starting	position
	     field1, and optional ending position field2 of a key field.  The
	     -k	option may be specified	multiple times,	in which case subse-
	     quent keys	are compared when earlier keys compare equal.  The -k
	     option replaces the obsolete options +pos1	and -pos2, but the old
	     notation is also supported.

     -t	char, --field-separator=char
	     Use char as a field separator character.  The initial char	is not
	     considered	to be part of a	field when determining key offsets.
	     Each occurrence of	char is	significant (for example, "charchar"
	     delimits an empty field).	If -t is not specified,	the default
	     field separator is	a sequence of blank space characters, and con-
	     secutive blank spaces do not delimit an empty field, however, the
	     initial blank space is considered part of a field when determin-
	     ing key offsets.  To use NUL as field separator, use -t '\0'.

     -z, --zero-terminated
	     Use NUL as	record separator.  By default, records in the files
	     are supposed to be	separated by the newline characters.  With
	     this option, NUL ('\0') is	used as	a record separator character.

     Other options:

	     Specify maximum number of files that can be opened	by sort	at
	     once.  This option	affects	behavior when having many input	files
	     or	using temporary	files.	The default value is 16.

	     Use PROGRAM to compress temporary files.  PROGRAM must compress
	     standard input to standard	output,	when called without arguments.
	     When called with argument -d it must decompress standard input to
	     standard output.  If PROGRAM fails, sort must exit	with error.
	     An	example	of PROGRAM that	can be used here is bzip2.

	     In	random sort, the file content is used as the source of the
	     'seed' data for the hash function choice.	Two invocations	of
	     random sort with the same seed data will use the same hash	func-
	     tion and will produce the same result if the input	is also	iden-
	     tical.  By	default, file /dev/random is used.

	     Print some	extra information about	the sorting process to the
	     standard output.

	     Take the input file list from the file filename.  The file	names
	     must be separated by NUL (like the	output produced	by the command
	     "find ... -print0").

	     Try to use	radix sort, if the sort	specifications allow.  The
	     radix sort	can only be used for trivial locales (C	and POSIX),
	     and it cannot be used for numeric or month	sort.  Radix sort is
	     very fast and stable.

	     Use mergesort.  This is a universal algorithm that	can always be
	     used, but it is not always	the fastest.

	     Try to use	quick sort, if the sort	specifications allow.  This
	     sort algorithm cannot be used with	-u and -s.

	     Try to use	heap sort, if the sort specifications allow.  This
	     sort algorithm cannot be used with	-u and -s.

     --mmap  Try to use	file memory mapping system call.  It may increase
	     speed in some cases.

     The following operands are	available:

     file    The pathname of a file to be sorted, merged, or checked.  If no
	     file operands are specified, or if	a file operand is -, the stan-
	     dard input	is used.

     A field is	defined	as a maximal sequence of characters other than the
     field separator and record	separator (newline by default).	 Initial blank
     spaces are	included in the	field unless -b	has been specified; the	first
     blank space of a sequence of blank	spaces acts as the field separator and
     is	included in the	field (unless -t is specified).	 For example, all
     blank spaces at the beginning of a	line are considered to be part of the
     first field.

     Fields are	specified by the -k field1[,field2] command-line option.  If
     field2 is missing,	the end	of the key defaults to the end of the line.

     The arguments field1 and field2 have the form m.n (m,n _ 0) and can be
     followed by one or	more of	the modifiers b, d, f, i, n, g,	M and r, which
     correspond	to the options discussed above.	 When b	is specified it	ap-
     plies only	to field1 or field2 where it is	specified while	the rest of
     the modifiers apply to the	whole key field	regardless if they are speci-
     fied only with field1 or field2 or	both.  A field1	position specified by
     m.n is interpreted	as the nth character from the beginning	of the mth
     field.  A missing .n in field1 means `.1',	indicating the first character
     of	the mth	field; if the -b option	is in effect, n	is counted from	the
     first non-blank character in the mth field; m.1b refers to	the first non-
     blank character in	the mth	field.	1.n refers to the nth character	from
     the beginning of the line;	if n is	greater	than the length	of the line,
     the field is taken	to be empty.

     nth positions are always counted from the field beginning,	even if	the
     field is shorter than the number of specified positions.  Thus, the key
     can really	start from a position in a subsequent field.

     A field2 position specified by m.n	is interpreted as the nth character
     (including	separators) from the beginning of the mth field.  A missing .n
     indicates the last	character of the mth field; m =	0 designates the end
     of	a line.	 Thus the option -k v.x,w.y is synonymous with the obsolete
     option +v-1.x-1 -w-1.y; when y is omitted,	-k v.x,w is synonymous with
     +v-1.x-1 -w.0.  The obsolete +pos1	-pos2 option is	still supported, ex-
     cept for -w.0b, which has no -k equivalent.

     LC_COLLATE	 Locale	settings to be used to determine the collation for
		 sorting records.

     LC_CTYPE	 Locale	settings to be used to case conversion and classifica-
		 tion of characters, that is, which characters are considered
		 whitespaces, etc.

		 Locale	settings that determine	the language of	output mes-
		 sages that sort prints	out.

     LC_NUMERIC	 Locale	settings that determine	the number format used in nu-
		 meric sort.

     LC_TIME	 Locale	settings that determine	the month format used in month

     LC_ALL	 Locale	settings that override all of the above	locale set-
		 tings.	 This environment variable can be used to set all
		 these settings	to the same value at once.

     LANG	 Used as a last	resort to determine different kinds of locale-
		 specific behavior if neither the respective environment vari-
		 able, nor LC_ALL are set.

     NLSPATH	 Path to NLS catalogs.

     TMPDIR	 Path to the directory in which	temporary files	will be
		 stored.  Note that TMPDIR may be overridden by	the -T option.

		 If defined -t will not	override the locale numeric symbols,
		 that is, thousand separators and decimal separators.  By de-
		 fault,	if we specify -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 sym-
		 bol was treated as both field separator and numeric separa-
		 tor, simultaneously.  This environment	variable enables the
		 old behavior.

     /var/tmp/.bsdsort.PID.*	       Temporary files.
     /dev/random		       Default seed file for the random	sort.

     The sort utility shall exit with one of the following values:

     0	   Successfully	sorted the input files or if used with -c or -C, the
	   input file already met the sorting criteria.
     1	   On disorder (or non-uniqueness) with	the -c or -C options.
     2	   An error occurred.

     comm(1), join(1), uniq(1)

     The sort utility is compliant with	the IEEE Std 1003.1-2008 ("POSIX.1")

     The flags [-ghRMSsTVz] are	extensions to the POSIX	specification.

     All long options are extensions to	the specification, some	of them	are
     provided for compatibility	with GNU versions and some of them are own ex-

     The old key notations +pos1 and -pos2 come	from older versions of sort
     and are still supported but their use is highly discouraged.

     A sort command first appeared in Version 1	AT&T UNIX.

     Gabor Kovesdan <>,

     Oleg Moskalenko <>

     This implementation of sort has no	limits on input	line length (other
     than imposed by available memory) or any restrictions on bytes allowed
     within lines.

     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 -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 specifica-
     tion, the simpler to process the lines the	faster the search will be.

     When sorting by arithmetic	value, using -n	results	in much	better perfor-
     mance than	-g so its use is encouraged whenever possible.

FreeBSD	13.0		       September 4, 2019		  FreeBSD 13.0


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