Running out of disk space

I am VPN into an Oracle database. I am running a simple select query but there are millions of records. I let it run for some time and it says my system is running out of disk space. Even if I stop the query, I don’t know if there are temporary files being written to my system. Does anyone know where they are? Is there any way to avoid this?

We do serialize records to disk on large datasets. This is more efficient than leaving everything in memory. The files are cleaned up when the editor is closed. They are written to normal user temp directory.