I am using socat to write to the stdin of a running docker container. The following code is working fine on Linux:
echo "ls" | socat EXEC:"docker attach container_name",pty STDIN &> /dev/null
On macos however the above doesn't work. I tried playing around with the settings but have not been able to get it to work.
I am using the following version:
$ brew info socat
==> socat: stable 1.8.0.1 (bottled)
When docker attach attempts to write to the PTY, it encounters a "Bad file descriptor" error because the write side isn't properly set up on MacOS.
So you need :
echo "ls" | socat EXEC:"docker attach container_name",pty - &> /dev/null
- meaning both standard input and standard output.
I don't see an easy way to get the exit code, one workaround is to pass it using standard output:
echo 'false; echo $?' | socat EXEC:"docker attach container_name",pty -