Linux Basic Operations 9 understanding and Learning Bash

A know bash this shell

1 management of the entire computer hardware is actually the operating system's core, this kernel needs to be protected, so our average user can only through the shell to communicate with the kernel, so that the kernel to achieve the work we want to hit.

2 as long as the interface of the application can be manipulated can be called shell

3 Bash Shell features

Command memory function history

command and file completion functions

Command alias Settings feature (alias)

Job control, front desk, background control

Program Scripts

Wildcard characters

Variable function of two shell

1 environment variables such as Path,home,mail,shell, and so on, in order to distinguish them from custom variables, environment variables are usually represented as uppercase characters

2 We can use the echo command to display the variable, but the variable must precede the character $ before it is displayed.

3 Basically, the order in which commands run can look like this

1 executing commands with a relative/absolute path

2 by alias find the command execution

3 executed by Bash's built-in command

4 by $path This variable in order to find a command to execute

4 Bash default key combination

CTRL + C terminate the current command

Ctrl+d input End EOF

Ctrl+m is just enter.

Ctrl+s pause the output of the screen

CTRL+Q restores the output of the screen

Ctrl+u the entire line of commands at the prompt

Ctrl+z suspend the current order

5 wildcard characters and special symbols

* Represents 0 to infinitely many arbitrary characters

? Representative must have one arbitrary character

[] The same representative must have a character within the brackets, for example [ABCD] represents one of the four

[-] For example [0-9] represents all numbers between 0-9

[^] For example [^ABC] Other characters that are non-ABC