-v /PATH/hostdir:/PATH/DIR 
默认 可读写
只读 ro
-v /PATH/hostdir:/PATH/DIR:ro


docker run --name docker_started -v /Users/dugang/tmp:/hosttmp -d -p 80:80 docker/getting-started 
http://127.0.0.1/


docker ps -a
docker ps 

docker exec -it docker_started /bin/sh

docker stop docker_started 
docker rm docker_started


docker run --name docker_started -v /Users/dugang/tmp:/hosttmp:ro -d -p 80:80 docker/getting-started 

cd /hosttmp
echo "hello3" > hello3.txt
/bin/sh: can't create hello3.txt: Read-only file system


使用busybox 
docker pull busybox
docker images
 docker images
REPOSITORY                    TAG       IMAGE ID       CREATED        SIZE
busybox                       latest    3c19bafed223   4 weeks ago    1.41MB

docker run --name mybusybox -v /Users/dugang/tmp:/hosttmp -it   busybox  /bin/sh