SHELL脚本中常用的控制结构
if ... then语句
if [ test_command ]
then
commands
fi
if ... then ... else语句
if [ test_command ]
then
commands
else
commands
fi
if ... then ... elif ... (else)语句
if [ test_command ]
then
commands
elif [ test_command ]
then
commands
...
...
else (optional)
commands
fi
for ... in语句
for 变量 in
变量列表
do
commands
done
while语句
while 条件为真
do
commands
done
until语句
until 条件为真
do
commands
done
case语句
case $variable in
match_1)
commands_to_execute_for_1;;
match_2)
commands_to_execute_for_2;;
match_3)
commands_to_execute_for_3;;
...
...
*) (可选 - any other value)
commands_to_execute_for_no_match
;;
esac