1. Assignment operator '=', without any space before and after;
a). var0=`commands` ###assign the results to variable with backquotes``
b). var1=$(commands) ###commands subsitution
eg. ###> arch=$(uname -m)
###>echo $arch
c). var2=234
d). var3="this is a string with whitespace, using double quoting to prevent words splitting"
e). var4='this line is not the same as above assignment,cause it's single quoting, not double'
f). a=2
let b=$a+1 ###if without 'let', errors, ( b = 2+1)
echo $b ### 3
2. Bash variables are untyped.
网友评论