Linux Command
ls
Show directory contents list
Supplementary instructions
ls command is the abbreviation of list, which is used to display the target list. It is a frequently used command in Linux. The output information of the ls command can be displayed with color highlighting to partition different types of files.
grammar
ls [options] [filename...]
[-1abcdfgiklmnopqrstuxABCDFGLNQRSUX] [-w cols] [-T cols] [-I pattern] [--full-time]
[--format={long,verbose,commas,across,vertical,single-col‐umn}]
[--sort={none,time,size,extension}] [--time={atime,access,use,ctime,status}]
[--color[={none,auto,always}]] [--help] [--version] [--]
Options
-C #Multiple column output, vertical sorting.
-F # Add "/" suffix to each directory name, add "|" suffix to each FIFO name, and add "*" suffix to each runnable name.
-R # Recursively list encountered subdirectories.
-a # List all files, including implicit files starting with ".".
-c # Use "state change time" instead of "file modification time" to sort (when using the "-t" option) or list (when using the "-l" option).
-d # List directory names like other files instead of listing their contents.
-i # Output the file serial number (i.e. i-node number: i-node number) before outputting the file. -l list (in single column format) file modes
# (file mode), the number of links to the file, owner name, group name, file size (in bytes), time information, and file name.
# By default, the time information displays the latest modification time; you can choose to display the other two time information with options "-c" and "-u". For device files,
# The area that originally displayed the file size usually displayed the major and minor device numbers (major and minor device numbers).
-q # Output non-printing characters in file names as question marks. (This is the default for output to the terminal.)
-r # Sort in reverse order.
-t # Sort by time information.
-u # Use the most recent access time instead of the most recent modification time to sort (when using the "-t" option) or list (when using the "-l" option).
-1 # Single column output.
-1, --format=single-column # Output one file per line (single column output). If standard output is not to a terminal, this option is the default.
-a, --all # List all files in the directory, including files starting with ".".
-b, --escape # List non-exportable characters in the file name using backslashes and character numbers (just like in C language).
-c, --time=ctime, --time=status
# Sort by file status change time (ctime in i node) and output in the directory
# Allow. If long format output is used (option "-l"), use the file's status change
# Change the time to replace the file modification time. [Translation Note: The so-called file status change (section i
# The ctime mark in the dot) includes both file modification and changes in file attributes (such as owner, group, number of links, etc.)]
-d, --directory
# List directory names like other files, rather than listing their contents.
-f # Do not sort directory contents; list them in the order they are stored on disk. At the same time, start the "-a" option, if there is "-l",
# "--color" or "-s" disable them.
-g # Ignore, for UNIX compatibility.
-i, --inode
# Print the i node number (also called file serial number and index num) on the left side of each file: file serial number and index num‐
#ber). The i-node number is unique within each specific file system.
-k, --kilobytes
# If file sizes are listed, they are in kilobytes KB.
-l, --format=long, --format=verbose
#The output information from left to right includes file name, file type, permissions, number of hard links, owner name, group name, size (byte)
# , and time information (if no other time is specified, it refers to the modification time). For files older than 6 months or beyond the future
# For 1-hour files, the hours and minutes in the time information will be replaced by the era.
#Before each directory is listed, there is a line of "Total Block Count" that displays the disk space occupied by all files in the directory. The block default is 1024 bytes;
# If the POSIXLY_CORRECT environment variable is set, the default block size is 512 bytes unless the "-k" option is used.
# Each hard link counts towards the total number of blocks (and therefore may be counted twice), which is definitely a disadvantage.
# Listed permissions are similar to specifications for symbolic (file) modes. But ls
# Combine multiple bits of information in the third character of each set of permissions, as follows: s If setuid is set
# bit or setgid bit, and the corresponding executable bit is also set. S if setuid bit or setgid is set
# bit, but the corresponding executable bit is not set. t If the sticky bit is set, and the corresponding executable bit is also set. T
# If the sticky bit is set, but the corresponding executable bit is not set. x
# If only the executable bit is set instead of the above four situations. - Other cases (i.e. the executable bit is not set).
-m, --format=commas
# List files horizontally, with as many lines per line as possible, separated by commas and a space.
-n, --numeric-uid-gid
# List numeric UIDs and GIDs instead of usernames and groupnames.
-o # List directory contents in long format, but do not display group information. Equivalent to using " --format=long --no-group
# ” option. This option is provided for compatibility with other versions of ls.
-p # Append a character after each file name to indicate the type of file. Similar to "-F" option but does not mark executable files.
-q, --hide-control-chars
# Use question marks to replace non-printing characters in file names. This is the default option.
-r, --reverse
# Arrange directory contents in reverse order.
-s, --size
# Output to the left of each file name the size of that file, in 1024-byte blocks. If POSIXLY_CORRECT is set
# environment variable, unless the " -k " option is used, the block size is 512 bytes.
-t, --sort=time
# Sort by the file's latest modification time (mtime in the i node) rather than by file name dictionary, with new files first.
-u, --time=atime, --time=access, --time=use
# Similar to option "-t", but uses the file's most recent access time (atime in the i node) instead of file modification
# Time change. If long format listing is used, the time printed is the most recent access time.
-w, --width cols
# Assume screen width is cols (cols replaced with actual numbers) columns. If this option is not used, the default value is this
# Obtained in this way: try to get it from the terminal driver first if possible, otherwise try to get it from the environment variable COLUMNS (if set
# If set), if it doesn't work, take 80.
-x, --format=across, --format=horizontal
#Multi-column output, sorted horizontally.
-A, --almost-all
# Display all files except "." and "..".
-B, --ignore-backups
# Do not output backup files ending with "~" unless given on the command line.
-C, --format=vertical
#Multi-column output, sorted vertically. This is the default when standard output is a terminal. When using the command names dir and d, it is always the default.
-D, --dired
# When outputting in long format ("-l" option), print an additional line after the main output: //DIRED// BEG1 END1 BEG2
#END2...
# BEGn and ENDn are unsigned integers, recording the starting and ending positions of each file name in the output (
# byte offset). This makes it easy for Emacs to find filenames even if they contain irregularities such as spaces or newlines.
# No special search is required for normal characters.
#
# If directories are listed recursively ("-R" option), list each subdirectory with a line similar to:
# //SUBDIRED// BEG1 END1 ... [Annotation: I tested TurboLinux4.0 and RedHat6.1 and found that they are both in "
# //DIRED// BEG1... " is listed after " //SUBDIRED// BEG1... ", that is, there is only one
# instead of after each subdirectory. And "//SUBDIRED//BEG1..." lists the offsets of each subdirectory name. 】
-F, --classify, --file-type
# Append a character after each file name to indicate the type of file. "*" represents an ordinary executable file; "/" represents a directory; "
# @ ” represents a symbolic link; “ | ” represents FIFOs; “ = ” represents sockets; nothing represents an ordinary file.
-G, --no-group
# Do not display group information when listing directories in long format.
-I, --ignorepattern
# Unless given on the command line, do not list matching shell file name patterns (pattern, not the general
# expression) file. In the shell, file names starting with "." do not match the file name pattern (pattern)
Matches wildcard characters starting with #.
-L, --dereference
# List information about the file pointed to by the symbolic link, not the symbolic link itself.
-N, --literal
# Do not use quotes around filenames.
-Q, --quote-name
# Enclose the file name in double quotes, and non-printing characters are represented in C language.
-R, --recursive
# List the contents of all directories recursively.
-S, --sort=size
# Sort directory contents by file size instead of lexicographically, with large files first.
-T, --tabsize cols
# Assume each tab width is cols . The default is 8. For efficiency, ls may use tab characters in the output. If cols is
0, tab characters are not used.
-U, --sort=none
# Directory contents are not sorted; listed in the order they are stored on disk. (Options "-U" and "-f" are not
# The former does not enable or disable related options. ) This is especially useful when listing very large directories because there is no sorting
# Can significantly speed up.
-X, --sort=extension
# Sort lexicographically by file extension (consisting of characters after the last "."). Those without extensions are listed first.
--color[=when]
# Specify whether to use color to distinguish file categories. The environment variable LS_COLORS specifies the colors used. How to set this variable see dir‐
# colors(1) . when can be omitted or one of the following:
none # Do not use color, this is the default.
# auto Use only when standard output is a terminal. always always uses color. Specifying --color and omitting when is equivalent to
# --color=always .
--full-time
# List full times instead of using standard abbreviations. The format is as in the default format of date(1); this format
# cannot be changed, but you can use cut(1) to extract the date string and send the result to the command "date -d".
# It is useful to include seconds in the output time. (Unix file systems store file time information accurate to the second.
# So this option already gives all the information the system knows. ) For example, when you have a Makefile
# This option helps when the file cannot be generated properly.
Parameters
Directory: Specify the directory to display the list, or it can be a specific file.
Example
$ ls # Only list visible files in the current directory
$ ls -l # List visible file details in the current directory
$ ls -hl # List details and display file size in readable size
$ ls -al # List detailed information of all files (including hidden)
$ ls --human-readable --size -1 -S --classify # Sort by file size
$ du -sh * | sort -h # Sort by file size (same as above)
Display a list of all files in the current directory including hidden files
[root@localhost ~]# ls -a
. anaconda-ks.cfg .bash_logout .bashrc install.log .mysql_history satools .tcshrc .vimrc
.. .bash_history .bash_profile .cshrc install.log.syslog .rnd .ssh .viminfo
Output long format list
[root@localhost ~]# ls -1
anaconda-ks.cfg
install.log
install.log.syslog
satools
Display the inode information of the file
Index node (index inode, referred to as "inode") is a special concept in Linux. Two texts with the same index node number are essentially the same file (except for different file names).
[root@localhost ~]# ls -i -l anaconda-ks.cfg install.log
2345481 -rw------- 1 root root 859 Jun 11 22:49 anaconda-ks.cfg
2345474 -rw-r--r-- 1 root root 13837 Jun 11 22:49 install.log
Horizontal output file list
[root@localhost /]# ls -m
bin, boot, data, dev, etc, home, lib, lost+found, media, misc, mnt, opt, proc, root, sbin, selinux, srv, sys, tmp, usr, var
Modify the last edited file
The most recently modified files are shown at the top.
[root@localhost /]# ls -t
tmp root etc dev lib boot sys proc data home bin sbin usr var lost+found media mnt opt selinux srv misc
Show recursive files
[root@localhost ~]# ls -R
.:
anaconda-ks.cfg install.log install.log.syslog satools
./satools:
black.txt freemem.sh iptables.sh lnmp.sh mysql php502_check.sh ssh_safe.sh
Print the UID and GID of a file
[root@localhost /]# ls -n
total 254
drwxr-xr-x 2 0 0 4096 Jun 12 04:03 bin
drwxr-xr-x 4 0 0 1024 Jun 15 14:45 boot
drwxr-xr-x 6 0 0 4096 Jun 12 10:26 data
drwxr-xr-x 10 0 0 3520 Sep 26 15:38 dev
drwxr-xr-x 75 0 0 4096 Oct 16 04:02 etc
drwxr-xr-x 4 0 0 4096 Jun 12 10:26 home
drwxr-xr-x 14 0 0 12288 Jun 16 04:02 lib
drwx------ 2 0 0 16384 Jun 11 22:46 lost+found
drwxr-xr-x 2 0 0 4096 May 11 2011 media
drwxr-xr-x 2 0 0 4096 Nov 8 2010 misc
drwxr-xr-x 2 0 0 4096 May 11 2011 mnt
drwxr-xr-x 2 0 0 4096 May 11 2011 opt
dr-xr-xr-x 232 0 0 0 Jun 15 11:04 proc
drwxr-x--- 4 0 0 4096 Oct 15 14:43 root
drwxr-xr-x 2 0 0 12288 Jun 12 04:03 sbin
drwxr-xr-x 2 0 0 4096 May 11 2011 selinux
drwxr-xr-x 2 0 0 4096 May 11 2011 srv
drwxr-xr-x 11 0 0 0 Jun 15 11:04 sys
drwxrwxrwt 3 0 0 98304 Oct 16 08:45 tmp
drwxr-xr-x 13 0 0 4096 Jun 11 23:38 usr
drwxr-xr-x 19 0 0 4096 Jun 11 23:38 var
List file and folder details
[root@localhost /]# ls -l
total 254
drwxr-xr-x 2 root root 4096 Jun 12 04:03 bin
drwxr-xr-x 4 root root 1024 Jun 15 14:45 boot
drwxr-xr-x 6 root root 4096 Jun 12 10:26 data
drwxr-xr-x 10 root root 3520 Sep 26 15:38 dev
drwxr-xr-x 75 root root 4096 Oct 16 04:02 etc
drwxr-xr-x 4 root root 4096 Jun 12 10:26 home
drwxr-xr-x 14 root root 12288 Jun 16 04:02 lib
drwx------ 2 root root 16384 Jun 11 22:46 lost+found
drwxr-xr-x 2 root root 4096 May 11 2011 media
drwxr-xr-x 2 root root 4096 Nov 8 2010 misc
drwxr-xr-x 2 root root 4096 May 11 2011 mnt
drwxr-xr-x 2 root root 4096 May 11 2011 opt
dr-xr-xr-x 232 root root 0 Jun 15 11:04 proc
drwxr-x--- 4 root root 4096 Oct 15 14:43 root
drwxr-xr-x 2 root root 12288 Jun 12 04:03 sbin
drwxr-xr-x 2 root root 4096 May 11 2011 selinux
drwxr-xr-x 2 root root 4096 May 11 2011 srv
drwxr-xr-x 11 root root 0 Jun 15 11:04 sys
drwxrwxrwt 3 root root 98304 Oct 16 08:48 tmp
drwxr-xr-x 13 root root 4096 Jun 11 23:38 usr
drwxr-xr-x 19 root root 4096 Jun 11 23:38 var
List readable file and folder details
[root@localhost /]# ls -lh
total 254K
drwxr-xr-x 2 root root 4.0K Jun 12 04:03 bin
drwxr-xr-x 4 root root 1.0K Jun 15 14:45 boot
drwxr-xr-x 6 root root 4.0K Jun 12 10:26 data
drwxr-xr-x 10 root root 3.5K Sep 26 15:38 dev
drwxr-xr-x 75 root root 4.0K Oct 16 04:02 etc
drwxr-xr-x 4 root root 4.0K Jun 12 10:26 home
drwxr-xr-x 14 root root 12K Jun 16 04:02 lib
drwx------ 2 root root 16K Jun 11 22:46 lost+found
drwxr-xr-x 2 root root 4.0K May 11 2011 media
drwxr-xr-x 2 root root 4.0K Nov 8 2010 misc
drwxr-xr-x 2 root root 4.0K May 11 2011 mnt
drwxr-xr-x 2 root root 4.0K May 11 2011 opt
dr-xr-xr-x 235 root root 0 Jun 15 11:04 proc
drwxr-x--- 4 root root 4.0K Oct 15 14:43 root
drwxr-xr-x 2 root root 12K Jun 12 04:03 sbin
drwxr-xr-x 2 root root 4.0K May 11 2011 selinux
drwxr-xr-x 2 root root 4.0K May 11 2011 srv
drwxr-xr-x 11 root root 0 Jun 15 11:04 sys
drwxrwxrwt 3 root root 96K Oct 16 08:49 tmp
drwxr-xr-x 13 root root 4.0K Jun 11 23:38 usr
drwxr-xr-x 19 root root 4.0K Jun 11 23:38 var
Show folder information
[root@localhost /]# ls -ld /etc/
drwxr-xr-x 75 root root 4096 Oct 16 04:02 /etc/
List file and folder details by time
[root@localhost /]# ls -lt
total 254
drwxrwxrwt 3 root root 98304 Oct 16 08:53 tmp
drwxr-xr-x 75 root root 4096 Oct 16 04:02 etc
drwxr-x--- 4 root root 4096 Oct 15 14:43 root
drwxr-xr-x 10 root root 3520 Sep 26 15:38 dev
drwxr-xr-x 14 root root 12288 Jun 16 04:02 lib
drwxr-xr-x 4 root root 1024 Jun 15 14:45 boot
drwxr-xr-x 11 root root 0 Jun 15 11:04 sys
dr-xr-xr-x 232 root root 0 Jun 15 11:04 proc
drwxr-xr-x 6 root root 4096 Jun 12 10:26 data
drwxr-xr-x 4 root root 4096 Jun 12 10:26 home
drwxr-xr-x 2 root root 4096 Jun 12 04:03 bin
drwxr-xr-x 2 root root 12288 Jun 12 04:03 sbin
drwxr-xr-x 13 root root 4096 Jun 11 23:38 usr
drwxr-xr-x 19 root root 4096 Jun 11 23:38 var
drwx------ 2 root root 16384 Jun 11 22:46 lost+found
drwxr-xr-x 2 root root 4096 May 11 2011 media
drwxr-xr-x 2 root root 4096 May 11 2011 mnt
drwxr-xr-x 2 root root 4096 May 11 2011 opt
drwxr-xr-x 2 root root 4096 May 11 2011 selinux
drwxr-xr-x 2 root root 4096 May 11 2011 srv
drwxr-xr-x 2 root root 4096 Nov 8 2010 misc
List file and folder details by modification time
[root@localhost /]# ls -ltr
total 254
drwxr-xr-x 2 root root 4096 Nov 8 2010 misc
drwxr-xr-x 2 root root 4096 May 11 2011 srv
drwxr-xr-x 2 root root 4096 May 11 2011 selinux
drwxr-xr-x 2 root root 4096 May 11 2011 opt
drwxr-xr-x 2 root root 4096 May 11 2011 mnt
drwxr-xr-x 2 root root 4096 May 11 2011 media
drwx------ 2 root root 16384 Jun 11 22:46 lost+found
drwxr-xr-x 19 root root 4096 Jun 11 23:38 var
drwxr-xr-x 13 root root 4096 Jun 11 23:38 usr
drwxr-xr-x 2 root root 12288 Jun 12 04:03 sbin
drwxr-xr-x 2 root root 4096 Jun 12 04:03 bin
drwxr-xr-x 4 root root 4096 Jun 12 10:26 home
drwxr-xr-x 6 root root 4096 Jun 12 10:26 data
dr-xr-xr-x 232 root root 0 Jun 15 11:04 proc
drwxr-xr-x 11 root root 0 Jun 15 11:04 sys
drwxr-xr-x 4 root root 1024 Jun 15 14:45 boot
drwxr-xr-x 14 root root 12288 Jun 16 04:02 lib
drwxr-xr-x 10 root root 3520 Sep 26 15:38 dev
drwxr-x--- 4 root root 4096 Oct 15 14:43 root
drwxr-xr-x 75 root root 4096 Oct 16 04:02 etc
drwxrwxrwt 3 root root 98304 Oct 16 08:54 tmp
Sort files by special characters
[root@localhost nginx-1.2.1]# ls -F
auto/ CHANGES CHANGES.ru conf/ configure* contrib/ html/ LICENSE Makefile man/ objs/ README src/
List files and mark color categories
[root@localhost nginx-1.2.1]# ls --color=auto
auto CHANGES CHANGES.ru conf configure contrib html LICENSE Makefile man objs README src
