Linux continues to learn bash features (20170420)

Command aliases

Alias aliases = ' '

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

To permanently use aliases in the shell, you need to change the configuration file

Alias displays all aliases that can now be used if no parameters are added later

Command substitution

$ (command), anti-quote

File name wildcard globbing

*: can match any character of any length

？ : can match any character (only one character)

"": matches any single character within the specified range

[^]: matches any single character outside the specified range

": Space:" White space character

": punct:" Punctuation

": Lower:" Lowercase letters

": Upper:" Uppercase

": Alpha:" Uppercase and lowercase letters

": Digit:" number

": Alnum:" Numbers and uppercase and lowercase letters

Man 7 Glob can display a wildcard help

Quotes supported by bash

' Command Replace '

"" Weak reference, you can implement variable substitution

' Strong reference, do not complete variable substitution

Linux continues to learn bash features (20170420)