Parallel devices 'file'

I wasn’t sure how to write the title of this thread, it’s the best I can come up with given my limited knowledge. I am attempting to send data out through the parallel port of a RiscPC using the command *copy filename parallel: where filename is the name of the data file. The response is

Copy file ADFS::HardDisc4.$.MOVE as devices:$.Parallel (Y/N/Quiet/Abandon) ?

Responding with Y, the computer then asks

File devices:$.Parallel already exists. Overwrite (Y/N) ?

I am not brave enough to respond with Y.

First, is it safe to overwrite?
Second, I assume this ‘file’ is in the DeviceFS, but can it be read?