10.1.3 Sorting the output

These options change the order in which ls sorts the information it outputs. By default, sorting is done by character code (e.g., ASCII order).

‘-c’

‘--time=ctime’

‘--time=status’

If the long listing format (e.g., -l, -o) is being used, print the status change timestamp (the ctime) instead of the mtime. When explicitly sorting by time (--sort=time or -t) or when not using a long listing format, sort according to the ctime. See File timestamps.

‘-f’

Primarily, like -U—do not sort; list the files in whatever order they are stored in the directory. But also enable -a (list all files) and disable -l, --color, and -s (if they were specified before the -f).

‘-r’

‘--reverse’

Reverse whatever the sorting method is—e.g., list files in reverse alphabetical order, youngest first, smallest first, or whatever.

‘-S’

‘--sort=size’

Sort by file size, largest first.

‘-t’

‘--sort=time’

Sort by modification timestamp (mtime), newest first. See File timestamps.

‘-u’

‘--time=atime’

‘--time=access’

‘--time=use’

If the long listing format (e.g., --format=long) is being used, print the last access timestamp (the atime). When explicitly sorting by time (--sort=time or -t) or when not using a long listing format, sort according to the atime. See File timestamps.

‘-U’

‘--sort=none’

Do not sort; list the files in whatever order they are stored in the directory. (Do not do any of the other unrelated things that -f does.) This is especially useful when listing very large directories, since not doing any sorting can be noticeably faster.

‘-v’

‘--sort=version’

Sort by version name and number, lowest first. It behaves like a default sort, except that each sequence of decimal digits is treated numerically as an index/version number. (See Details about version sort.)

‘-X’

‘--sort=extension’

Sort directory contents alphabetically by file extension (characters after the last ‘.’); files with no extension are sorted first.