std io lost between agent and runtime

[shsjshentao]

take a container stdout example

1. agent receive container stdout from fifo in vm
2. agent listen unix and send stdout to runtime with vsock
3. runtime receive stdout and send to fifo on host
4. user can read logs from fifo

Now, if user stop read logs from fifo for a while, then read fifo file again, user cannot receive logs any longer.

I found agent show log "write vsock hypervisor(0):11001->host(2):1073741828: broken pipe", and runtime receive a EOF and exit io proxy

[kzys]

Thanks for reporting! Let me take a look next week.