Linux common Commands-command line editing, history, command line shortcut keys, Pstree,alias, command substitution, wildcard characters

command-line editing:
Cursor Jump:
CTRL + A: Skip to the beginning of the command
Ctrl+e: Jump to the end of the command line
Ctrl+u: Delete the cursor to the beginning of the command line
CTRL+K: Delete the cursor to the end of the command line
Ctrl+l: Clear Screen
Ctrl+d: Delete the contents after the cursor

Command history:
View command history: Historical
-C: Empty command history
-D OFFSET [n]: Delete command at specified position
-W: Save the Command history to the history file

Environment variables
Path: Command Search Path
Histsize: Command history buffer size

The use of command history tips:
!n: Executes the nth command in the command history;

[Email protected] ~]$!1
Whatis Mans
Man (1)-format and display the on-line manual pages
Man (1p)-Display system documentation
Man (7)-Macros to format mans pages
Man.config [Man] (5)-Configuration data for Mans
Man [Manpath] (1)-format and display the on-line manual pages
Man-pages (7)-Conventions for writing Linux mans pages
[Email protected] ~]$ history
1 Whatis Mans

!-n: Executes the reciprocal nth command in the command history;

Whatis Mans
History
[Email protected] ~]$!-2
Whatis Mans
Man (1)-format and display the on-line manual pages
Man (1p)-Display system documentation
Man (7)-Macros to format mans pages
Man.config [Man] (5)-Configuration data for Mans
Man [Manpath] (1)-format and display the on-line manual pages
Man-pages (7)-Conventions for writing Linux mans pages

!: Executes the previous command;

[[email protected] ~]$!!
Whatis Mans
Man (1)-format and display the on-line manual pages
Man (1p)-Display system documentation
Man (7)-Macros to format mans pages
Man.config [Man] (5)-Configuration data for Mans
Man [Manpath] (1)-format and display the on-line manual pages
Man-pages (7)-Conventions for writing Linux mans pages

!string: The most recent command in the command history that starts with a specified string

[Email protected] ~]$!man
Mans
[Email protected] ~]$
[Email protected] ~]$

!$: References the last parameter of the previous command;

[Email protected] ~]$ ls/tmp/
ABC inittabl.2 KEYRING-C6BPQR ORBIT-GDM pulse-y030ipht7unr test
Hi keyring-11uhbi keyring-hxk4gf orbit-rhel rc Virtual-rhel. T2nxt0
Inittab KEYRING-4AFGVD KEYRING-TTIDCT passwd rc.2
Inittab.1 keyring-6hak4z keyring-v1ncmd PULSE-KYYFFO5RNHPL rc.3
[email protected] ~]$ ll!$
ll/tmp/
Total 84
Drwxr-xr-x. 2 root root 4096 Nov 20:26 ABC
Drwxr-xr-x. 2 root root 4096 Nov 20:28 hi
-rw-r--r--. 1 root root 884 Nov 02:59 Inittab
Drwxr-xr-x. 2 root root 4096 Nov 21:01 inittab.1
Drwxr-xr-x. 2 root root 4096 Nov 21:01 inittabl.2
DRWX------. 2 Rhel rhel 4096 Nov 17:54 Keyring-11uhbi
DRWX------. 2 Rhel rhel 4096 June KEYRING-4AFGVD

Esc. Same as!$

ALT +. (remote terminal not supported)

Command completion:
PATH:
Path Completion:

Pstree: Show Process Tree

NAME
Pstree-display a tree of processes

[Email protected] ~]$ Pstree
Init─┬─networkmanager─┬─dhclient
│└─{networkmanager}
├─abrtd
├─acpid
├─atd
├─AUDITD───{AUDITD}
├─bonobo-activati───{bonobo-activat}
├─clock-applet
├─CONSOLE-KIT-DAE───63*[{CONSOLE-KIT-DA}]
├─crond
├─cupsd
├─2*[dbus-daemon───{dbus-daemon}]
├─2*[dbus-launch]
├─devkit-power-da
├─gconfd-2

History: Command Historical use

[Email protected] ~]$ history
1 Whatis Mans
2 whatis/etc/passwd
3 Mans Whatis
4 Whatis CD
5 Whatis ls
6 Whatis Type
7 Whatis du
8 Whatis Echo
9 Whatis MV
Ten Whatis Man
One man cut
Cut-d:/etc/passwd
Cut-d:-f1/etc/passwd

-C: Clear History

-N: Delete the specified location command

-W: Save command to History file

Command aliases
Alias cmdalias= ' COMMAND [options] [arguments] '
Aliases defined in the shell are valid only for the current shell life cycle, and the valid range of aliases is only the current shell process;

[[email protected] ~]$ alias
Alias l.= ' ls-d. *--color=auto '
Alias ll= ' Ls-l--color=auto '
Alias ls= ' ls--color=auto '
Alias Vi= ' Vim '
Alias Which= ' Alias | /usr/bin/which--tty-only--read-alias--show-dot--show-tilde '
[Email protected] ~]$

[[Email protected] ~]$ type alias
Alias is a shell builtin
[email protected] ~]$ Help alias
Alias:alias [-P] [Name[=value] ...]
Define or display aliases.

Without arguments, ' alias ' prints the list of aliases in the reusable
Form ' Alias Name=value ' on standard output.

Otherwise, an alias was defined for each NAME whose the VALUE is given.
A trailing space in VALUE causes the next word to being checked for
Alias substitution when the alias is expanded.

Options:
-P Print all defined aliases in a reusable format

Exit Status:
Alias returns True unless a NAME is supplied for which no alias have been
Defined.
[Email protected] ~]$

Canceling command aliases

Ualias Cmdalias

Use the original command

\cmd

[Email protected] ~]$ \ls/tmp/
ABC inittabl.2 KEYRING-C6BPQR ORBIT-GDM pulse-y030ipht7unr test
Hi keyring-11uhbi keyring-hxk4gf orbit-rhel rc Virtual-rhel. T2nxt0
Inittab KEYRING-4AFGVD KEYRING-TTIDCT passwd rc.2
Inittab.1 keyring-6hak4z keyring-v1ncmd PULSE-KYYFFO5RNHPL rc.3
[Email protected] ~]$

Command substitution: $ (command), anti-quote: ' command '
To replace a subcommand in a command with the process of executing the result
File-2013-02-28-14-53-31.txt

Quotes supported by bash:
": Command substitution

[Email protected] ~]$ echo "dir is ' pwd '"
Dir Is/home/rhel
[Email protected] ~]$ cd/tmp/
[Email protected] tmp]$ echo "dir is ' pwd '"
Dir is/tmp
[Email protected] tmp]$

"": weak reference, can implement variable substitution

[Email protected] tmp]$ echo "The path is $PATH"
The path Is/usr/lib64/qt-3.3/bin:/usr/local/bin:/bin:/usr/bin:/usr/local/sbin:/usr/sbin:/sbin:/home/rhel/bin
[Email protected] tmp]$

': Strong reference, do not complete variable substitution

[Email protected] tmp]$ echo ' The path is $PATH '
The path is $PATH
[Email protected] tmp]$

File name wildcard, globbing
*: Any character of any length
?: any single character
[]: matches any single character within the specified range
[ABC], [A-m], [A-z], [A-z], [0-9], [a-za-z], [0-9a-za-z]
[: Space:]: white space character
[:p UNCT:]: Punctuation
[: Lower:]: lowercase letters
[: Upper:]: Uppercase
[: Alpha:]: Uppercase and lowercase letters
[:d igit:]: Number
[: Alnum:]: Numbers and uppercase and lowercase letters

# Man 7 Glob
[^]: matches any single character outside the specified range

[[: Alpha:]]*[[:space:]]*[^[:alpha:]]

Practice:
1, create A123, Cd6, c78m, C1 My, m.z, K, 8yu, 789 and other documents; Note that the above files are separated by commas, and the other symbols are part of the file name;
2. Display all files beginning with a or m;
LS [am]*
3. Display all files containing numbers in the file name;
LS *[0-9]*
LS *[[:d igit:]]*
4. Display all files that end with a number and do not contain a blank in the file name;
LS *[^[:space:]]*[0-9]?????????
5. display files with special symbols of non-letters or numbers in the file name;
LS *[^[:alnum:]]*

Linux common Commands-command line editing, history, command line shortcut keys, Pstree,alias, command substitution, wildcard characters