10.1.2 What information is listed

These options affect the information that ls displays. By default, only file names are shown.

`--author'

List each file's author when producing long format directory listings. In GNU/Hurd, file authors can differ from their owners, but in other operating systems the two are the same.

`-D'

`--dired'

With the long listing (`-l') format, print an additional line after the main output:

//DIRED// beg1 end1 beg2 end2 ...

The begN and endN are unsigned integers that record the byte position of the beginning and end of each file name in the output. This makes it easy for Emacs to find the names, even when they contain unusual characters such as space or newline, without fancy searching.

If directories are being listed recursively (-R), output a similar line with offsets for each subdirectory name:

//SUBDIRED// beg1 end1 ...

Finally, output a line of the form:

//DIRED-OPTIONS// --quoting-style=word

where word is the quoting style (see section 10.1.7 Formatting the file names).

Here is an actual example:

$ mkdir -p a/sub/deeper a/sub2 $ touch a/f1 a/f2 $ touch a/sub/deeper/file $ ls -gloRF --dired a a: total 8 -rw-r--r-- 1 0 Nov 9 18:30 f1 -rw-r--r-- 1 0 Nov 9 18:30 f2 drwxr-xr-x 3 4096 Nov 9 18:30 sub/ drwxr-xr-x 2 4096 Nov 9 18:30 sub2/ a/sub: total 4 drwxr-xr-x 2 4096 Nov 9 18:30 deeper/ a/sub/deeper: total 0 -rw-r--r-- 1 0 Nov 9 18:30 file a/sub2: total 0 //DIRED// 55 57 98 100 141 144 186 190 252 258 327 331 //SUBDIRED// 2 3 195 200 263 275 335 341 //DIRED-OPTIONS// --quoting-style=literal

Note that the pairs of offsets on the `//DIRED//' line above delimit these names: `f1', `f2', `sub', `sub2', `deeper', `file'. The offsets on the `//SUBDIRED//' line delimit the following directory names: `a', `a/sub', `a/sub/deeper', `a/sub2'.

Here is an example of how to extract the fifth entry name, `deeper', corresponding to the pair of offsets, 252 and 258:

$ ls -gloRF --dired a > out $ dd bs=1 skip=252 count=6 < out 2>/dev/null; echo deeper

Note that although the listing above includes a trailing slash for the `deeper' entry, the offsets select the name without the trailing slash. However, if you invoke ls with `--dired' along with an option like `--escape' (aka `-b') and operate on a file whose name contains special characters, notice that the backslash is included:

$ touch 'a b' $ ls -blog --dired 'a b' -rw-r--r-- 1 0 Nov 9 18:41 a\ b //DIRED// 40 44 //DIRED-OPTIONS// --quoting-style=escape

If you use a quoting style that adds quote marks (e.g., `--quoting-style=c'), then the offsets include the quote marks. So beware that the user may select the quoting style via the environment variable QUOTING_STYLE. Hence, applications using `--dired' should either specify an explicit `--quoting-style=literal' option (aka `-N' or `--literal') on the command line, or else be prepared to parse the escaped names.

`--full-time'

Produce long format directory listings, and list times in full. It is equivalent to using `--format=long' with `--time-style=full-iso' (see section 10.1.6 Formatting file timestamps).

`-g'

Produce long format directory listings, but don't display owner information.

`-G'

`--no-group'

Inhibit display of group information in a long format directory listing. (This is the default in some non-GNU versions of ls, so we provide this option for compatibility.)

`-h'

`--human-readable'

Append a size letter to each size, such as `M' for mebibytes. Powers of 1024 are used, not 1000; `M' stands for 1,048,576 bytes. This option is equivalent to `--block-size=human' (see section 2.2 Block size). Use the `--si' option if you prefer powers of 1000.

`-i'

`--inode'

Print the inode number (also called the file serial number and index number) of each file to the left of the file name. (This number uniquely identifies each file within a particular filesystem.)

`-l'

`--format=long'

`--format=verbose'

In addition to the name of each file, print the file type, permissions, number of hard links, owner name, group name, size, and timestamp (see section 10.1.6 Formatting file timestamps), normally the modification time.

Normally the size is printed as a byte count without punctuation, but this can be overridden (see section 2.2 Block size). For example, `-h' prints an abbreviated, human-readable count, and `--block-size="'1"' prints a byte count with the thousands separator of the current locale.

For each directory that is listed, preface the files with a line `total blocks', where blocks is the total disk allocation for all files in that directory. The block size currently defaults to 1024 bytes, but this can be overridden (see section 2.2 Block size). The blocks computed counts each hard link separately; this is arguably a deficiency.

The permissions listed are similar to symbolic mode specifications (see section 26.2 Symbolic Modes). But ls combines multiple bits into the third character of each set of permissions as follows:

`s'

If the setuid or setgid bit and the corresponding executable bit are both set.

`S'

If the setuid or setgid bit is set but the corresponding executable bit is not set.

`t'

If the sticky bit and the other-executable bit are both set.

`T'

If the sticky bit is set but the other-executable bit is not set.

`x'

If the executable bit is set and none of the above apply.

`-'

Otherwise.

Following the permission bits is a single character that specifies whether an alternate access method applies to the file. When that character is a space, there is no alternate access method. When it is a printing character (e.g., `+'), then there is such a method.

`-n'

`--numeric-uid-gid'

Produce long format directory listings, but display numeric UIDs and GIDs instead of the owner and group names.

`-o'

Produce long format directory listings, but don't display group information. It is equivalent to using `--format=long' with `--no-group' .

`-s'

`--size'

Print the disk allocation of each file to the left of the file name. This is the amount of disk space used by the file, which is usually a bit more than the file's size, but it can be less if the file has holes.

Normally the disk allocation is printed in units of 1024 bytes, but this can be overridden (see section 2.2 Block size).

For files that are NFS-mounted from an HP-UX system to a BSD system, this option reports sizes that are half the correct values. On HP-UX systems, it reports sizes that are twice the correct values for files that are NFS-mounted from BSD systems. This is due to a flaw in HP-UX; it also affects the HP-UX ls program.

`--si'

Append an SI-style abbreviation to each size, such as `MB' for megabytes. Powers of 1000 are used, not 1024; `MB' stands for 1,000,000 bytes. This option is equivalent to `--block-size=si'. Use the `-h' or `--human-readable' option if you prefer powers of 1024.