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 time (the ‘ctime’ in the inode) instead of
the modification time.
When explicitly sorting by time (--sort=time or -t)
or when not using a long listing format,
sort according to the status change time.
- ‘-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 time (the ‘mtime’ in the inode), newest first.
- ‘-u’
- ‘--time=atime’
- ‘--time=access’
- ‘--time=use’
- If the long listing format (e.g., --format=long) is being used,
print the last access time (the ‘atime’ in the inode).
When explicitly sorting by time (--sort=time or -t)
or when not using a long listing format, sort according to the access time.
- ‘-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.