README.md

Variables

Local Variables

    a=123	#int
    echo a  #print a
    echo $a #print 123

    hello="Hello            World"
    echo $hello		#Print Hello World
    echo ${hello}	#Print Hello World
    echo "$hello"	#Print Hello            World
    echo "${hello}"	#Print Hello            World
    echo '$hello'	#Print $hello
    echo '${hello}'	#Print ${hello}

    echo ${#hello}	#Prints the length of the variable

    FILE="test1 test2.txt"
    wc -m $FILE   # attempts to count char of 2 files: `test1` and `test2.txt`
    wc -m "$FILE" # attempts to count char of 1 files: `test1 test2.txt`

Set Local Variables & Scope

    #local var='local varaible'
    func1(){
        local var='func1 local'
        echo "In func1, var = '$var'"
        func2
    }

    func2(){
        echo "In func2, var = '$var'"
    }

    local var=global # as global
    func1

    echo "Global var = '$var'"

Environment Variables

Parameter	Description
$HOME	The current user's home directory.
$PATH	A colon-separated list of directories in which the shell looks for commands.
$PWD	The current working directory.
$RANDOM	Random integer between 0 and 32767.
$UID	The numeric, real user ID of the current user.

Read More

Set Environment Variables

    export VARNAME="my value" 

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