Shell Script Summary 2

Echo ' seq-s ' 10 '--command to use anti-quote
echo $ (seq-s "" 10)

(())
Let
Expr
BC--Features support for fractional counting
$[]

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[Email protected] ~]# ((ruan=1*8-9))
[Email protected] ~]# echo $ruan
-1
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[Email protected] ~]# b=$ ((1*2+3))
[Email protected] ~]# echo $b
5
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[Email protected] shell_ruanjp]# i=2
[[email protected] shell_ruanjp]# let i=i+8
[Email protected] shell_ruanjp]# echo $i
10
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[Email protected] ~]# echo "SCALE=2;5/3" |BC
1.66
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Read-p "Pls input a number:" Var
READ-T 3-p "pls input a number:"--3 seconds timeout exit

&/dev/null--its role

[< test expression;]
Test-f file && echo 1| | Echo 0
Test! -F file && echo 1| | Echo 0
--equal to the above
[-f file.txt] && echo 1| | Echo 0

File Test Operators

While True
Do
Code Layer
Done

Shell Script Summary 2