Published Book on Amazon
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All of IOT Starting with the Latest Raspberry Pi from Beginner to Advanced – Volume 1 |
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All of IOT Starting with the Latest Raspberry Pi from Beginner to Advanced – Volume 2 |
출판된 한글판 도서
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최신 라즈베리파이(Raspberry Pi)로 시작하는 사물인터넷(IOT)의 모든 것 – 초보에서 고급까지 (상) |
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최신 라즈베리파이(Raspberry Pi)로 시작하는 사물인터넷(IOT)의 모든 것 – 초보에서 고급까지 (하) |
Original Book Contents
8.2 Shell Program
8.2.1 Shell and BASH (Bourne Again Shell)
When we execute a command in the Terminal program, the Shell program accepts and interprets the command internally, instructs the system kernel to process it, and when processing is complete, it receives the result from the kernel and returns it to the Terminal program. Since the Shell is between the Terminal and system kernels, and handles all requests that the Terminal program requires, the Terminal program does not need to know anything about the system kernel. It is called a Shell in the sense that it serves to provide the necessary services to external Terminals that needs to receive services from the kernel while enclosing the system kernel as if the clamShell surrounds the contents.
The Terminal program provides a Shell to communicate with the system, where the input command is passed directly to the connected Shell program.
The most popular Shell program on Linux is BASH (Bourne Again Shell). It is specified as the default Shell in most distributions, so you do not have to think about anything else unless it's a special case. BASH not only provides the essential basic functions necessary to execute commands, but also provides a variety of additional functions required by users.