SORT(1) 						    BSD General Commands Manual 						   SORT(1)

NAME

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

SYNOPSIS

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

DESCRIPTION

     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
     '' character (-z option).  A record can contain any printable or unprintable characters.  Comparisons are based on one or more sort keys
     extracted from each line of input, and are performed lexicographically, according to the current locale's collating rules and the specified
     command-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 output.

     -S size, --buffer-size=size
	     Use size for the maximum size of the memory buffer.  Size modifiers %,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 buffer, 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 and equal key.	This is a non-standard feature,
	     but it is widely accepted and used.

     --version
	     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 comparisons.

     -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, which have a much permissive format
	     than those allowed by -n, but it has a significant performance drawback.

     -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 positive);
	     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 option is use-
	     ful 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 thousand separators).

     -R, --random-sort, --sort=random
	     Sort by a random order.  This is a random permutation of the inputs 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 compared by their prefixes and versions (leading zeros are ignored in ver-
	     sion numbers, see example below).	If an input string does not match the pattern, then it is compared using the byte compare func-
	     tion.  All string comparisons are performed in C locale, the locale environment setting is ignored.

	     Example:

	     $ ls sort* | sort -V

	     sort-1.022.tgz

	     sort-1.23.tgz

	     sort-1.23.1.tgz

	     sort-1.024.tgz

	     sort-1.024.003.

	     sort-1.024.003.tgz

	     sort-1.024.07.tgz

	     sort-1.024.009.tgz

     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 argument
	     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 subsequent 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 consecutive blank spaces do not delimit an empty field, however, the
	     initial blank space is considered part of a field when determining key offsets.  To use NUL as field separator, use -t ''.

     -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 ('') is used as a record separator character.

     Other options:

     --batch-size=num
	     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.

     --compress-program=PROGRAM
	     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.

     --random-source=filename
	     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 function and will produce the same result if the input is also identical.  By
	     default, file /dev/random is used.

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

     --files0-from=filename
	     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").

     --radixsort
	     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.

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

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

     --heapsort
	     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 standard
	     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 applies 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 specified 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 sup-
     ported, except for -w.0b, which has no -k equivalent.

ENVIRONMENT

     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 classification of characters, that is, which characters are considered white-
		 spaces, etc.

     LC_MESSAGES
		 Locale settings that determine the language of output messages that sort prints out.

     LC_NUMERIC  Locale settings that determine the number format used in numeric sort.

     LC_TIME	 Locale settings that determine the month format used in month sort.

     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.

     LANG	 Used as a last resort to determine different kinds of locale-specific behavior if neither the respective environment variable,
		 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.

     GNUSORT_NUMERIC_COMPATIBILITY
		 If defined -t will not override the locale numeric symbols, that is, thousand separators and decimal separators.  By default, 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 symbol was treated as both field separator and numeric separator, simultaneously.  This
		 environment variable enables the old behavior.

FILES

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

EXIT STATUS

     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.

SEE ALSO

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

STANDARDS

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

     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
     extensions.

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

HISTORY

     A sort command first appeared in Version 3 AT&T UNIX.

AUTHORS

     Gabor Kovesdan <gabor@FreeBSD.org>,

     Oleg Moskalenko <mom040267@gmail.com>

NOTES

     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 specification, the simpler to process the lines the faster the search will
     be.

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

BSD
								   July 3, 2012 							       BSD