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This article shows you what the shell variables $#,$@,$0,$1,$2 mean. The content is concise and easy to understand. It will definitely make your eyes shine. I hope you can learn something through the detailed introduction of this article.

load.sh script is as follows: #!/ bin/bashset -ucurrent_dir=$(cd `dirname $0`; pwd)python ${current_dir}/curl.pyhive -f ${current_dir}/../ hive/load_cms.sql$0: The filename of the Shell itself

The shell variables $#,$@,$0,$1,$2 in Linux are explained:

Variable description:

$$

PID of Shell itself (ProcessID)

$!

PID of Shell Last Run Background Process

$?

End code of last command run (return value)

$-

List of flags set using the Set command

$*

List of all parameters. If "$*" is enclosed by "", output all parameters as "$1 $2 … $n".

$@

List of all parameters. If "$@" is enclosed by "", output all parameters as "$1" "$2" … "$n".

$#

Number of parameters added to Shell

$0

File name of Shell itself

$1~$n

Parameter values added to the Shell.$ 1 is the first parameter,$2 is the second parameter…

What does the shell variable $#,$@,$0,$1,$2 mean? Have you learned any knowledge or skills? If you want to learn more skills or enrich your knowledge reserves, please pay attention to the industry information channel.

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