【shell】基礎から立ちかえる1

#!/bin/bash

echo 'hello world!'

$ chmod +x stest.sh
$ ./stest.sh
hello world!

#!/bin/bash

echo 'hello world!'
pwd
echo \
    'I' \
    'love' \
    'shell' \
    'script' \
echo
'End world!'

#!/bin/bash

var='value'
echo $var

var='change'
echo $var

#!/bin/bash

readonly var='value'
var='fuga'

var='set'
echo $var
unset var
echo $var

var=value
echo $var
var='hoge fuga'
echo $var
var=hoge fuga
echo $var

empty=''
echo \$empty: $empty
empty=
echo \$empty: $empty
echo \$undefined: $undefined

var=value
echo $var
echo \$var
echo \$var $var
echo \\

var=hoge\ fuga
echo $var

var1=value
var2='${var1}'
echo $var2

var1=value
var2="${var1}"
echo $var2

var1='hoge''fuga'
echo '$var1': $var1

var2=hoge
var3=$var1$var2
echo '$var3': $var3

echo "\$var1hoge": $var1hoge
echo "\$var1'hoge'": $var1'hoge'
echo "\${var1}hoge": ${var1}hoge
echo "\${var1}'hoge'": ${var1}'hoge'

echo '$1': $1
echo '${1}': ${2}
echo '"$3"': "$3"
echo '${10}': ${10}
echo '${11}': ${11}
echo '$10': $10

echo $0
echo $1

echo '入力値' $1
exit $1

echo ----------
echo 引数の数 $#
echo '$1'の値 $1
echo '$2'の値 $2
shift
echo $?
echo ----------
echo 引数の数 $#
echo '$1'の値 $1
echo '$2'の値 $2
shift
echo $?
echo ----------
echo 引数の数 $#
echo '$1'の値 $1
echo '$2'の値 $2
shift
echo $?
echo ----------

function echo_args() {
    echo '引数の数' $#
    echo '$1'の値 $1
    echo '$2'の値 $2
    echo '$3'の値 $3
    echo ----------
}

echo '"$@"'の場合
echo_args "$@"
echo '"$*"'の場合
echo_args "$*"

echo $$

(sleep 10; echo 'end') &
echo $!
wait $!