Shell Foundation: Shell is the user interface of the system, which provides an interface for users to interact with the kernel. It receives the command entered by the user and feeds it into the kernel to execute. We followed the Shell's grammar script and passed it on to Shell,shell to explain to us the contents of nuclear energy identification in the system, and the kernel then controlled the computer hardware to execute the scripts. The shell is actually a command interpreter that interprets the commands entered by the user and sends them to the kernel. In addition, the shell has its own programming language for editing commands, which allows the user to write programs composed of Shell commands. Shell programming languages have many features of a common programming language, such as a looping structure and branching control structures, and shell programs written in this programming language have the same effect as other applications. Second, create and execute the shell script:
" \033[31m hello,world \033[0m"
How to execute the script:
1. Bash Interpretation execution:
Bash hello.sh
2. Script Add Execute permission:
755 hello.sh # Plus Execute permissions source hello.sh # Execute program
Order of execution of the command:
1, command path >>>2, alias >>>3, Bash Path command >>>4, environment variable corresponding command
Third, view the history command:
Linux Shell Basics
