[Happy BASH] BASH中的$*和$@的区别

首先来看一段BASH代码：

echo "\$@=" $@
echo "\"\$@\"=" "$@"

echo "print each param from \$@"
for var in $@
do
        echo $var
done

echo "print each param from \"\$@\""
for var in "$@"
do
        echo "$var"
done

echo "print each param from \$*"
for var in $*
do
        echo "$var"
done

echo "print each param from \"\$*\""
for var in "$*"
do
        echo "$var"
done

执行./test.sh "a a" b c d，将会得到以下输出：

$@= a a b c d
"$@"= a a b c d
print each param from $@
a
a
b
c
d
print each param from "$@"
a a
b
c
d
print each param from $*
a
a
b
c
d
print each param from "$*"
a a b c d

总结，总是要用"$@" （双括号括起来的$@），所有参数的串联字符串，则用"$*" （仍然是双括号括起来的$*）。