ls Command

Purpose

Displays the contents of a directory.

Syntax

To display contents of directory or name of file

ls [ -1 ] [ -A ] [ -C ] [ -E ] [ -F ] [-H  | -L ] [ -N ] [ -R ] [ -S ] [ -X] [ -a ] [ -b ] [ -c ] [ -d ] [ -e ] [ -f ] [ -g ] [ -i ] [-k] [ -l ] [ -m ] [ -n ] [ -o ] [ -p ] [ -q ] [ -r ] [ -s ] [ -t ] [ -u ] [ -U ] [ -x ] [ File ... ]

To display contents of directory

ls -f [ -C ] [ -d ] [ -i ] [ -m ] [ -s ] [ -X] [ -x ] [ -1 ] [ -U ] [ Directory ... ]

Description

The ls command writes to standard output the contents of each specified Directory parameter or the name of each specified File parameter, along with any other information you ask for with the flags. If you do not specify a File or Directory parameter, the ls command displays the contents of the current directory.

Specifying more than one of the options in the mutually exclusive pairs is not considered an error. The last option that is specified in each pair determines the output format.

By default, the ls command displays all information in alphabetic order by file name. The collating sequence is determined by the LANG or LC_COLLATE environment variable.

When the ls command displays the contents of a directory, it does not show entries for files whose names begin with a . (dot) unless you use the -a or -A flag. If the command is run by root, it uses the -A flag by default.

There are three main ways to format the output:

• List one entry per line.
• List entries in multiple columns by specifying either the -C or -x flag. The -C flag is the default format when output is to a tty. The ls command displays single column output if file or directory names are too long.
• List entries in a comma-separated series by specifying the -m flag.

To determine the number of character positions in the output line, the ls command uses the COLUMNS environment variable. If this variable is not set, the command gets the current column value of the display. If the ls command cannot determine the number of character positions by either of these methods, it uses a default value of 80.

Encryption takes precedence over the presence of the Access Control Lists (ACLs) and other EAs.

The mode that is displayed with the -e and -l flags is interpreted as follows:

The next nine characters are divided into three sets of three characters each. The first set of three characters show the owner's permission. The next set of three characters show the permission of the other users in the group. The last set of three characters shows the permission of anyone else with access to the file. The three characters in each set indicate read, write, and execute permission of the file. Execute permission of a directory allows searching a directory for a specified file.

Permissions are indicated as follows:

The group-execute permission character is s if the file has set-group-ID mode. The user-execute permission character is s if the file has set-user-ID mode. The last character of the mode (usually x or -) is T if the 01000 (octal) bit of the mode is set. The indications of set-ID and 01000 bit of the mode are capitalized (S and T) if the corresponding execute permission is not set. The mode t indicates that the sticky bit is on for the file or the directory.

The mode that is displayed with the -e flag is the same as with the -l flag, except for the addition of an 11th character that is interpreted as follows.

When the capacity of the files in a directory is listed, the ls command displays a total count of blocks, including indirect blocks.

Flags

ls  -p |  pr  -5  -t  -w80

Exit Status

This command returns the following exit values:

Examples

1. To list all files in the current directory, enter the following command:

   ls -a

   This command lists all files, including . (dot), .. (dot-dot), and other files with names that begin with a dot.

2. To display detailed information, enter the following command:

   ls -l chap1 .profile

   This command displays a long listing with detailed information about chap1 and .profile.

3. To display detailed information about a directory, enter the following command:

   ls -d -l . manual manual/chap1

   This command displays a long listing for the directories . and manual, and for the file manual/chap1. Without the -d flag, this command lists the files in the . and manual directories instead of the detailed information about the directories themselves.

4. To list the files in order of modification time, enter the following command:

   ls -l -t

   This command displays a long listing of the files that were modified most recently, followed by the older files.

5. To display detailed information with expanded user and group name, enter the following command:

   ls -lX .profile

   This command displays a long listing with detailed information about .profile.

6. To display data about whether extended attributes are set for the files in the current directory, enter the following command:

   ls -U

7. To display information about the number of files system blocks in units of 512 bytes for the files in the current directory, enter the following command:

   ls -l

   Example output:

   total 16
   -rw-r--r--    1 root     system           22 Feb 05 05:29 sample1
   -rw-r--r--    1 root     system           12 Feb 05 05:29 sample2

8. To display information about the number of files system blocks in units of 1024 bytes for the files in the current directory, enter the following command:

    ls -lk

   Example output:

   total 8
   -rw-r--r--    1 root     system           22 Feb 05 05:29 sample1
   -rw-r--r--    1 root     system           12 Feb 05 05:29 sample2

Files