Published Book on Amazon
All of IOT Starting with the Latest Raspberry Pi from Beginner to Advanced – Volume 1 | |
All of IOT Starting with the Latest Raspberry Pi from Beginner to Advanced – Volume 2 |
출판된 한글판 도서
최신 라즈베리파이(Raspberry Pi)로 시작하는 사물인터넷(IOT)의 모든 것 – 초보에서 고급까지 (상) | |
최신 라즈베리파이(Raspberry Pi)로 시작하는 사물인터넷(IOT)의 모든 것 – 초보에서 고급까지 (하) |
Original Book Contents
10.6 Commands Related to Selective Execution
Normally, when a command is processed normally, the exit status is set to zero, which is ㅅtreated as "True". On the other hand, if the command is not processed normally, the exit status is set to a non-zero value, which is treated as "False".
10.6.1 "&&" Command - Execute Command by "and" Method
This command processes the next command if the first command is processed normally, and sets the exit status by "and" operation according to the final processing result of the both commands.
[Command Format]
< command-1> && < command-2> |
[Detail Description]
command-1 | command-2 | Exit status | |||||
exec. | result | True/False | exec. | result | True/False | operat. | final |
Yes | Ok | True | Yes | Ok/Error | True/False | and | True/False |
Yes | Error | False | No | - | - | and | False |
Command-2 is executed if the processing of the command-1 is "True", and Command-2 is not executed when the processing of the command-1 is "False".
The exit status is set to "True" if the exit status of both <command-1> and <command-2> is "True", or set to "False".