SORT(1) | General Commands Manual | SORT(1) |
sort
—
sort |
[-bdfHilmnrSsu ] [-k
kstart[, kend]]
[-o output]
[-R char]
[-T dir]
[-t char]
[file ...] |
sort |
-C |-c
[-bdfilnru ] [-k
kstart[, kend]
[-t char]]
[-R char]
[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.-c
sort
produces the appropriate error messages and
exits with code 1; otherwise, sort
returns 0.
sort
-c
produces no
output. See also -u
.-H
sort
.-m
-o
output-S
-s
sort
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.)-r
The 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
.
TMPDIR
sort
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 9.4 |