added -t1 flag explanation to docs

Signed-off-by: bota <[email protected]>

Author: SergiuBota1

docs/book/v1/commands.md

@@ -28,3 +28,5 @@ In both cases the flags are optional. Keep in mind if both `start` and `end` are
 In order to be able to test the `processed` command, by default when processing the "control" message, it is logged as successfully processed with `"levelName":"info"` simulating that the message was processed successfully. To use it run the following message:
 
 `echo "control" | socat -t1 - TCP:host:port`
+
+Using `-t1` flag is not necessary but can be useful, it is used to set a timeout of n seconds for both reading and writing, after n second of inactivity, socat will terminate the connection. If the timeout is not set and the server does not respond or keep the connection open, the socat process could hang indefinitely.