Section: User Commands (1)
Updated: February 2019
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column - columnate lists  


column [options] [file...]  


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
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.  


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.


The environment variable COLUMNS is used to determine the size of the screen if no other information is available.  


The column command appeared in 4.3BSD-Reno.  


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.  


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  


colrm(1), ls(1), paste(1), sort(1)  


The column command is part of the util-linux package and is available from