Supply package:io-streams

Connects an InputStream to an OutputStream without passing the end-of-stream notification through to the OutputStream. Use this to supply an OutputStream with multiple InputStreams and use connect for the final InputStream to finalize the OutputStream, like so:
do Streams.supply  input1 output
Streams.supply  input2 output
Streams.connect input3 output
supply with the arguments flipped.