# attach Usage: docker attach [OPTIONS] CONTAINER Attach to a running container --no-stdin=false Do not attach STDIN --sig-proxy=true Proxy all received signals to the process The `docker attach` command allows you to attach to a running container using the container's ID or name, either to view its ongoing output or to control it interactively. You can attach to the same contained process multiple times simultaneously, screen sharing style, or quickly view the progress of your daemonized process. You can detach from the container and leave it running with `CTRL-p CTRL-q` (for a quiet exit) or with `CTRL-c` if `--sig-proxy` is false. If `--sig-proxy` is true (the default),`CTRL-c` sends a `SIGINT` to the container. > **Note:** > A process running as PID 1 inside a container is treated specially by > Linux: it ignores any signal with the default action. So, the process > will not terminate on `SIGINT` or `SIGTERM` unless it is coded to do > so. It is forbidden to redirect the standard input of a `docker attach` command while attaching to a tty-enabled container (i.e.: launched with `-t`). #### Examples $ docker run -d --name topdemo ubuntu /usr/bin/top -b $ docker attach topdemo top - 02:05:52 up 3:05, 0 users, load average: 0.01, 0.02, 0.05 Tasks: 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 20 0 17200 1116 912 R 0 0.3 0:00.03 top top - 02:05:55 up 3:05, 0 users, load average: 0.01, 0.02, 0.05 Tasks: 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 20 0 17208 1144 932 R 0 0.3 0:00.03 top top - 02:05:58 up 3:06, 0 users, load average: 0.01, 0.02, 0.05 Tasks: 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 20 0 17208 1144 932 R 0 0.3 0:00.03 top ^C$ $ echo $? 0 $ docker ps -a | grep topdemo 7998ac8581f9 ubuntu:14.04 "/usr/bin/top -b" 38 seconds ago Exited (0) 21 seconds ago topdemo And in this second example, you can see the exit code returned by the `bash` process is returned by the `docker attach` command to its caller too: $ docker run --name test -d -it debian 275c44472aebd77c926d4527885bb09f2f6db21d878c75f0a1c212c03d3bcfab $ docker attach test $$ exit 13 exit $ echo $? 13 $ docker ps -a | grep test 275c44472aeb debian:7 "/bin/bash" 26 seconds ago Exited (13) 17 seconds ago test