FileSink.ref

For FIFOs & pipes, keep Bun's process alive until the pipe closes.

By default, this is managed automatically: while the stream is open the process stays alive, and once the other end hangs up or the stream closes, the process exits.

If you previously called unref, call this to re-enable automatic management.

Internally, calls to ref and unref are reference counted. The count starts at 1.

If the file is not a FIFO or pipe, ref and unref do nothing. If the pipe is already closed, this does nothing.