| SORT(1) | General Commands Manual | SORT(1) | 
sort —
| sort | [ -bdfHilmnrSsu] [-kkstart[,kend]]
      [-ooutput]
      [-Rchar]
      [-Tdir]
      [-tchar]
      [file ...] | 
| sort | -C|-c[-bdfilnru] [-kkstart[,kend]
      [-tchar]]
      [-Rchar]
      [file] | 
sort utility sorts text files by lines. Comparisons
  are based on one or more sort keys extracted from each line of input, and are
  performed lexicographically. By default, if keys are not given,
  sort regards each input line as a single field.
The following options are available:
-C-c without the error messages in the
      case of unsorted input.-csort produces the appropriate error messages and
      exits with code 1; otherwise, sort returns 0.
      sort -c produces no
      output. See also -u.-Hsort.-m-o
    output-S-ssort implementations only.-T
    dirTMPDIR or /tmp if
      TMPDIR is not defined.-u-c option, check that there are no
      lines with duplicate keys.The following options, which should be given before any
    -k options, override the default ordering rules.
    When ordering options appear independent of, and before, key field
    specifications, the requested field ordering rules are applied globally to
    all sort keys. When attached to a specific key (see
    -k), the ordering options override all global
    ordering options for that key.
-d-f-i-l-n-n option no
      longer implies the -b option.)-rThe treatment of field separators can be altered using these options:
-b-b option specified before
      the first -k option applies globally to all
      -k options. Otherwise, the
      -b option can be attached independently to each
      field argument of the -k
      option (see below). Note that the -b option has no
      effect unless key fields are specified.-k
    kstart[,kend]-k option replaces the obsolescent options
      +pos1 and
      -pos2.-R
    char-R
      ⟨alphanumeric⟩ usually produces
      undesirable results. If char is not a single character, then it specifies
      the value of the desired record separator as an integer specified in any
      of the normal NNN, 0ooo, or 0xXXX ways, or as an octal value preceded by
      \. Caution: do not attempt to specify Ctl-A as “-R 1” which
      will not do what was intended at all! The default record separator is
      newline.-t
    char-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; further, the
      initial blank space is considered part of a field when
      determining key offsets.The following operands are available:
-, the
      standard input is used.A field is defined as a minimal sequence of characters followed by a field separator or a newline character. By default, the first blank space of a sequence of blank spaces acts as the field separator. All blank spaces in a sequence of blank spaces are considered as part of the next field; 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
    kstart[,kend] argument. A
    missing kend argument defaults to the end of a
  line.
The arguments kstart and
    kend have the form
    m.n and
    can be followed by one or more of the letters b,
    d, f,
    i, l,
    n, and r, which correspond
    to the options discussed above. A kstart position
    specified by
    m.n
    (m, n >
    0) is interpreted as the nth character in the
    mth field. A missing
    .n in
    kstart 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.
A kend position specified by
    m.n is
    interpreted as the nth character (including
    separators) 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 obsolescent option
    +v-1.x-1-w-1.y;
    when y is omitted, -k
    v.x,w
    is synonymous with
    +v-1.x-1-w+1.0.
    The obsolescent +pos1
    -pos2 option is still
    supported, except for
    -w.0b,
    which has no -k equivalent.
sort compares records by comparing the key
    fields selected by -k arguments, from first given to
    last, until discovering a difference. If there are no
    -k arguments, the whole record is treated as a
    single key. After exhausting the -k arguments, if no
    difference has been found, then the result depends upon the
    -u and -S option settings.
    With -u the records are considered identical, and
    one is suppressed. Otherwise with -s set (default)
    the records are left in their original order, or with
    -S (posix mode) the whole record is considered as a
    tie breaker.
sort.
TMPDIRsort uses the contents of the
      TMPDIR environment variable as the path in which
      to store temporary files.-c (or
      -C) option.sort command appeared in
  Version 1 AT&T UNIX. This
  sort implementation appeared in
  4.4BSD and is used since NetBSD
  1.6.
sort has no limits on input line length (other than
  imposed by available memory) or any restrictions on bytes allowed within
  lines.
To protect data sort
    -o calls
    link(2) and
    unlink(2), and thus fails on
    protected directories.
Input files should be text files. If file doesn't end with record
    separator (which is typically newline), the sort
    utility silently supplies one.
The current sort uses lexicographic radix
    sorting, which requires that sort keys be kept in memory (as opposed to
    previous versions which used quick and merge sorts and did not.) Thus
    performance depends highly on efficient choice of sort keys, and the
    -b option and the kend
    argument of the -k option should be used whenever
    possible. Similarly, sort
    -k1f is equivalent to sort
    -f and may take twice as long.
| September 1, 2019 | NetBSD 10.0 |