@gotcha is correct. In Concourse there is no way to transfer files to the host. One of the core design principles of Concourse is that tasks run in containers without leaving behind state.
In order to pass artefacts between steps in a job you can use task inputs/outputs. When you
get resources at the start of a job this makes them available effectively like volume mounts on all subsequent
puts and in tasks which define that resources as an input. When a task defines an output then this directory is subsequently mounted on every put/task with that named input.
In order to pass artefacts between jobs you will need to
put to a resource in the first job then
get from that resource in the subsequent job. Doing an
scp from a task to transfer to the outside world would be considered an antipattern since it could result in two runs of a job with the same inputs yielding different results.
As a side note, Concourse doesn’t actually use Docker to start containers. Instead it uses Garden.