COLUMN
Section: User Commands (1)
Updated: February 2019
Page Index
NAME
column - columnate lists
SYNOPSIS
column [options]
[
file...]
DESCRIPTION
The
column
utility formats its input into multiple columns. The util support three modes:
- columns are filled before rows
-
This is the default mode (required by backward compatibility).
- rows are filled before columns
-
This mode is enabled by option -x, --fillrows
- table
-
Determine the number of columns the input contains and create a table. This
mode is enabled by option -t, --table and columns formatting is
possible to modify by --table-* options. Use this mode if not sure.
Input is taken from file, or otherwise from standard input. Empty lines
are ignored and all invalid multibyte sequences are encoded by \x<hex> convention.
OPTIONS
The argument
columns for
--table-* options is comma separated
list of the column names as defined by
--table-columns or it's column
number in order as specified by input. It's possible to mix names and numbers.
- -J, --json
-
Use JSON output format to print the table, the option
--table-columns is required and the option --table-name is recommended.
- -c, --output-width width
-
Output is formatted to a width specified as number of characters. The original
name of this option is --columns; this name is deprecated since v2.30. Note that input
longer than width is not truncated by default.
- -d, --table-noheadings
-
Do not print header.
This option allows the use of logical column names on the command line,
but keeps the header hidden when printing the table.
- -o, --output-separator string
-
Specify the columns delimiter for table output (default is two spaces).
- -s, --separator separators
-
Specify the possible input item delimiters (default is whitespace).
- -t, --table
-
Determine the number of columns the input contains and create a table.
Columns are delimited with whitespace, by default, or with the characters
supplied using the --output-separator option.
Table output is useful for pretty-printing.
- -N, --table-columns names
-
Specify the columns names by comma separated list of names. The names are used
for the table header or to address column in option arguments.
- -R, --table-right columns
-
Right align text in the specified columns.
- -T, --table-truncate columns
-
Specify columns where text can be truncated when necessary, otherwise
very long table entries may be printed on multiple lines.
- -E, --table-noextreme columns
-
Specify columns where is possible to ignore unusually long (longer than
average) cells when calculate column width. The option has impact to the width
calculation and table formatting, but the printed text is not affected.
The option is used for the last visible column by default.
- -e, --table-header-repeat
-
Print header line for each page.
- -W, --table-wrap columns
-
Specify columns where is possible to use multi-line cell for long text when
necessary.
- -H, --table-hide columns
-
Don't print specified columns. The special placeholder '-' may be used to
hide all unnamed columns (see --table-columns).
- -O, --table-order columns
-
Specify columns order on output.
- -n, --table-name name
-
Specify the table name used for JSON output. The default is "table".
- -L, --table-empty-lines
-
Insert empty line to the table for each empty line on input. The default
is ignore empty lines at all.
- -r, --tree column
-
Specify column to use tree-like output. Note that the circular dependencies and
other anomalies in child and parent relation are silently ignored.
- -i, --tree-id column
-
Specify column with line ID to create child-parent relation.
- -p, --tree-parent column
-
Specify column with parent ID to create child-parent relation.
- -x, --fillrows
-
Fill rows before filling columns.
- -V, --version
-
Display version information and exit.
- -h, --help
-
Display help text and exit.
ENVIRONMENT
The environment variable
COLUMNS is used to determine the size of
the screen if no other information is available.
HISTORY
The column command appeared in 4.3BSD-Reno.
BUGS
Version 2.23 changed the
-s
option to be non-greedy, for example:
printf "a:b:c\n1::3\n" | column -t -s ':'
Old output:
a b c
1 3
New output (since util-linux 2.23):
a b c
1 3
Historical versions of this tool indicated that "rows are filled before
columns" by default, and that the
-x
option reverses this. This wording did not reflect the actual behavior, and it
has since been corrected (see above). Other implementations of
column
may continue to use the older documentation, but the behavior should be
identical in any case.
EXAMPLES
Print fstab with header line and align number to the right:
sed 's/#.*//' /etc/fstab | column --table --table-columns SOURCE,TARGET,TYPE,OPTIONS,PASS,FREQ --table-right PASS,FREQ
Print fstab and hide unnamed columns:
sed 's/#.*//' /etc/fstab | column --table --table-columns SOURCE,TARGET,TYPE --table-hide -
Print a tree:
echo -e '1 0 A\n2 1 AA\n3 1 AB\n4 2 AAA\n5 2 AAB' | column --tree-id 1 --tree-parent 2 --tree 3
1 0 A
2 1 |-AA
4 2 | |-AAA
5 2 | `-AAB
3 1 `-AB
SEE ALSO
colrm(1),
ls(1),
paste(1),
sort(1)
AVAILABILITY
The column command is part of the util-linux package and is available from
https://www.kernel.org/pub/linux/utils/util-linux/.