attach 只要用于重新登录一个正在执行的容器，如果容器没有在运行那么先start
Usage: docker attach [OPTIONS] CONTAINER
Attach to a running container
--no-stdin=falseDonot attach STDIN
--sig-proxy=trueProxy all received signals to the process (even in non-TTY mode). SIGCHLD, SIGKILL,and SIGSTOP are not proxied.
The attach 让你能够查看登录到容易, detached (-d) or interactive (-i). 你可以在容器执行时查看当前容器中执行的进程
使用 CTRL-C 快捷键来直接退出(for a quiet exit) or CTRL-\. 这个快捷键将能让你在退出时，保持一个单步跟踪。
stop一个容器, use docker stop.
杀死一个容器, use docker kill.
Examples:
$ ID=$(sudo docker run -d ubuntu /usr/bin/top -b)
$ sudo docker attach $ID
top -02:05:52 up 3:05,0 users, load average:0.01,0.02,0.05Tasks:1 total,1 running,0 sleeping,0 stopped,0 zombie
Cpu(s):0.1%us,0.2%sy,0.0%ni,99.7%id,0.0%wa,0.0%hi,0.0%si,0.0%st
Mem:373572k total,355560k used,18012k free,27872k buffers
Swap:786428k total,0k used,786428k free,221740k cached
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
1 root 200172001116912 R 00.30:00.03 top
top -02:05:55 up 3:05,0 users, load average:0.01,0.02,0.05Tasks:1 total,1 running,0 sleeping,0 stopped,0 zombie
Cpu(s):0.0%us,0.2%sy,0.0%ni,99.8%id,0.0%wa,0.0%hi,0.0%si,0.0%st
Mem:373572k total,355244k used,18328k free,27872k buffers
Swap:786428k total,0k used,786428k free,221776k cached
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
1 root 200172081144932 R 00.30:00.03 top
top -02:05:58 up 3:06,0 users, load average:0.01,0.02,0.05Tasks:1 total,1 running,0 sleeping,0 stopped,0 zombie
Cpu(s):0.2%us,0.3%sy,0.0%ni,99.5%id,0.0%wa,0.0%hi,0.0%si,0.0%st
Mem:373572k total,355780k used,17792k free,27880k buffers
Swap:786428k total,0k used,786428k free,221776k cached
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
1 root 200172081144932 R 00.30:00.03 top
^C$
$ sudo docker stop $ID