Shell quotes those things

#通配符 {} * []?

1.1 The difference between quotation marks and unquoted 1:

[[email protected] ~]# touch a B

[email protected] ~]# LL

Total 0

-rw-r--r--. 1 root root 0 June 16:25 a

-rw-r--r--. 1 root root 0 June 16:25 b

[[email protected] ~]# touch "a B"

[email protected] ~]# LL

Total 0

-rw-r--r--. 1 root root 0 June 16:25 a

-rw-r--r--. 1 root root 0 June 16:25 a B

-rw-r--r--. 1 root root 0 June 16:25 b

1.2 The difference between quotation marks and unquoted 2:

[email protected] tmp]# LL

Total dosage 0

-rw-r--r--1 root root 0 June 25 19:36?

-rw-r--r--1 root root 0 June 25 19:32 *

-rw-r--r--1 root root 0 June 19:33 AA

-rw-r--r--1 root root 0 June 19:33 ABC

-rw-r--r--1 root root 0 June 19:33 b

[email protected] tmp]# ll?

-rw-r--r--1 root root 0 June 25 19:36?

-rw-r--r--1 root root 0 June 25 19:32 *

-rw-r--r--1 root root 0 June 19:33 b

[email protected] tmp]# ll "?"

-rw-r--r--1 root root 0 June 25 19:36?

[email protected] tmp]# LL *

-rw-r--r--1 root root 0 June 25 19:36?

-rw-r--r--1 root root 0 June 25 19:32 *

-rw-r--r--1 root root 0 June 19:33 AA

-rw-r--r--1 root root 0 June 19:33 ABC

-rw-r--r--1 root root 0 June 19:33 b

[[email protected] tmp]# ll "*"

-rw-r--r--1 root root 0 June 25 19:32 *

1.3 double quotes and single quotation marks difference 1:

About $

[Email protected] ~]# echo "$LANG"

en_US. UTF-8

[Email protected] ~]# echo ' $LANG '

$LANG

1.4 double quotes and single quotation marks difference 2:

About ' '

[Email protected] ~]# echo "' which awk '"

/bin/awk

[[email protected] ~]# echo ' which awk '

' Which awk '

1.5 double quotes and single quotation marks difference 3:

About!

[[email protected] ~]# echo '!ll '

!ll

[Email protected] ~]# echo "!ll"

echo "Ll/bin/awk"

Ll/bin/awk

Shell quotes those things