NAME

ls — list directory contents

SYNOPSIS

ls	[ -ABCFGHILPRSTUWZabcdfghiklmnopqrstuwxy1,][ -D format][ file ...]

DESCRIPTION

For each operand that names a file of a type other than directory, ls displays its name as well as any requested, associated information. For each operand that names a file of type directory, ls displays the names of files contained within that directory, as well as any requested, associated information.

If no operands are given, the contents of the current directory are displayed. If more than one operand is given, non-directory operands are displayed first; directory and non-directory operands are sorted separately and in lexicographical order.

The following options are available:

-A: Include directory entries whose names begin with a dot (‘ .’) except for . and ... Automatically set for the super-user unless -I is specified.
-B: Force printing of non-printable characters (as defined by ctype(3) and current locale settings) in file names as \ xxx, where xxx is the numeric value of the character in octal.
-C: Force multi-column output; this is the default when output is to a terminal.
-D format: When printing in the long ( -l) format, use format to format the date and time output. The argument format is a string used by strftime(3). Depending on the choice of format string, this may result in a different number of columns in the output. This option overrides the -T option.
-F: Display a slash (‘ /’) immediately after each pathname that is a directory, an asterisk (‘ *’) after each that is executable, an at sign (‘ @’) after each symbolic link, an equals sign (‘ =’) after each socket, a percent sign (‘ %’) after each whiteout, and a vertical bar (‘ |’) after each that is a FIFO.
-G: Enable colorized output. This option is equivalent to defining CLICOLOR in the environment. (See below.) This functionality can be compiled out by removing the definition of COLORLS.
-H: Symbolic links on the command line are followed. This option is assumed if none of the -F, -d, or -l options are specified.
-I: Prevent -A from being automatically set for the super-user.
-L: If argument is a symbolic link, list the file or directory the link references rather than the link itself. This option cancels the -P option.
-P: If argument is a symbolic link, list the link itself rather than the object the link references. This option cancels the -H and -L options.
-R: Recursively list subdirectories encountered.
-S: Sort by size (largest file first) before sorting the operands in lexicographical order.
-T: When printing in the long ( -l) format, display complete time information for the file, including month, day, hour, minute, second, and year. The -D option gives even more control over the output format.
-U: Use time when file was created for sorting or printing.
-W: Display whiteouts when scanning directories.
-Z: Display each file's MAC label; see maclabel(7).
-a: Include directory entries whose names begin with a dot (‘ .’).
-b: As -B, but use C escape codes whenever possible.
-c: Use time when file status was last changed for sorting or printing.
-d: Directories are listed as plain files (not searched recursively).
-f: Output is not sorted.
-g: This option is deprecated and is only available for compatibility with 4.3BSD; it was used to display the group name in the long ( -l) format output.
-h: When used with the -l option, use unit suffixes: Byte, Kilobyte, Megabyte, Gigabyte, Terabyte and Petabyte in order to reduce the number of digits to four or fewer using base 2 for sizes.
-i: For each file, print the file's file serial number (inode number).
-k: This has the same effect as setting environment variable BLOCKSIZE to 1024, except that it also nullifies any -h options to its left.
-l: (The lowercase letter “ell”.) List files in the long format, as described in the The Long Format subsection below.
-m: Stream output format; list files across the page, separated by commas.
-n: Display user and group IDs numerically rather than converting to a user or group name in a long ( -l) output.
-o: Include the file flags in a long ( -l) output. See chflags(1) for a list of file flags and their meanings.
-p: Write a slash (‘ /’) after each filename if that file is a directory.
-q: Force printing of non-graphic characters in file names as the character ‘ ?’; this is the default when output is to a terminal.
-r: Reverse the order of the sort.
-s: Display the number of blocks used in the file system by each file. Block sizes and directory totals are handled as described in The Long Format subsection below, except (if the long format is not also requested) the directory totals are not output when the output is in a single column, even if multi-column output is requested.
-t: Sort by descending time modified (most recently modified first). If two files have the same modification timestamp, sort their names in ascending lexicographical order. The -r option reverses both of these sort orders.
Note that these sort orders are contradictory: the time sequence is in descending order, the lexicographical sort is in ascending order. This behavior is mandated by IEEE Std 1003.2 (“POSIX.2”). This feature can cause problems listing files stored with sequential names on FAT file systems, such as from digital cameras, where it is possible to have more than one image with the same timestamp. In such a case, the photos cannot be listed in the sequence in which they were taken. To ensure the same sort order for time and for lexicographical sorting, set the environment variable LS_SAMESORT or use the -y option. This causes ls to reverse the lexicographal sort order when sorting files with the same modification timestamp.
-u: Use time of last access, instead of time of last modification of the file for sorting ( -t) or printing ( -l).
-w: Force raw printing of non-printable characters. This is the default when output is not to a terminal.
-x: The same as -C, except that the multi-column output is produced with entries sorted across, rather than down, the columns.
-y: When the -t option is set, sort the alphabetical output in the same order as the time output. This has the same effect as setting LS_SAMESORT. See the description of the -t option for more details.
-1: (The numeric digit “one”.) Force output to be one entry per line. This is the default when output is not to a terminal.
-,: (Comma) When the -l option is set, print file sizes grouped and separated by thousands using the non-monetary separator returned by localeconv(3), typically a comma or period. If no locale is set, or the locale does not have a non-monetary separator, this option has no effect.

The -1, -C, -x, and -l options all override each other; the last one specified determines the format used.

The -c, -u, and -U options all override each other; the last one specified determines the file time used.

The -S and -t options override each other; the last one specified determines the sort order used.

The -B, -b, -w, and -q options all override each other; the last one specified determines the format used for non-printable characters.

The -H, -L and -P options all override each other (either partially or fully); they are applied in the order specified.

By default, ls lists one entry per line to standard output; the exceptions are to terminals or when the -C or -x options are specified.

File information is displayed with one or more <blank>s separating the information associated with the -i, -s, and -l options.

The Long Format

If the -l option is given, the following information is displayed for each file: file mode, number of links, owner name, group name, MAC label, number of bytes in the file, abbreviated month, day-of-month file was last modified, hour file last modified, minute file last modified, and the pathname.

If the modification time of the file is more than 6 months in the past or future, and the -D or -T are not specified, then the year of the last modification is displayed in place of the hour and minute fields.

If the owner or group names are not a known user or group name, or the -n option is given, the numeric ID's are displayed.

If the file is a character special or block special file, the device number for the file is displayed in the size field. If the file is a symbolic link the pathname of the linked-to file is preceded by “ ->”.

The listing of a directory's contents is preceded by a labeled total number of blocks used in the file system by the files which are listed as the directory's contents (which may or may not include . and .. and other files which start with a dot, depending on other options).

The default block size is 512 bytes. The block size may be set with option -k or environment variable BLOCKSIZE. Numbers of blocks in the output will have been rounded up so the numbers of bytes is at least as many as used by the corresponding file system blocks (which might have a different size).

The file mode printed under the -l option consists of the entry type and the permissions. The entry type character describes the type of file, as follows:

The next three fields are three characters each: owner permissions, group permissions, and other permissions. Each field has three character positions:

If r, the file is readable; if -, it is not readable.
If w, the file is writable; if -, it is not writable.
The first of the following that applies:

S

If in the owner permissions, the file is not executable and set-user-ID mode is set. If in the group permissions, the file is not executable and set-group-ID mode is set.

s

If in the owner permissions, the file is executable and set-user-ID mode is set. If in the group permissions, the file is executable and setgroup-ID mode is set.

x

The file is executable or the directory is searchable.

-

The file is neither readable, writable, executable, nor set-user-ID nor set-group-ID mode, nor sticky. (See below.)

These next two apply only to the third character in the last group (other permissions).

T

The sticky bit is set (mode 1000), but not execute or search permission. (See chmod(1) or sticky(7).)

t

The sticky bit is set (mode 1000), and is searchable or executable. (See chmod(1) or sticky(7).)

The next field contains a plus (‘ +’) character if the file has an ACL, or a space (‘ ’) if it does not. The ls utility does not show the actual ACL; use getfacl(1) to do this.

ENVIRONMENT

The following environment variables affect the execution of ls:

EXIT STATUS

The ls utility exits 0 on success, and >0 if an error occurs.

EXAMPLES

List the contents of the current working directory in long format:

$ ls -l

In addition to listing the contents of the current working directory in long format, show inode numbers, file flags (see chflags(1)), and suffix each filename with a symbol representing its file type:

$ ls -lioF

List the files in /var/log, sorting the output such that the mostly recently modified entries are printed first:

$ ls -lt /var/log

COMPATIBILITY

The group field is now automatically included in the long listing for files in order to be compatible with the IEEE Std 1003.2 (“POSIX.2”) specification.

STANDARDS

With the exception of options -I, -g, -n and -o, the ls utility conforms to IEEE Std 1003.1-2001 (“POSIX.1”).

The ACL support is compatible with IEEE Std 1003.2c (“POSIX.2c”) Draft 17 (withdrawn).

HISTORY

An ls command appeared in Version 1 AT&T UNIX.

BUGS

To maintain backward compatibility, the relationships between the many options are quite complex.

The exception mentioned in the -s option description might be a feature that was based on the fact that single-column output usually goes to something other than a terminal. It is debatable whether this is a design bug.

IEEE Std 1003.2 (“POSIX.2”) mandates opposite sort orders for files with the same timestamp when sorting with the -t option.

YOS OPENSONAR