pub fn write_message<W: Write, T: Serialize>(
writer: &mut W,
message: &T,
) -> Result<()>Expand description
Write one JSON-RPC message as a single newline-terminated line, then
flush. Callers pass the single locked stdout handle owned by
super::serve; nothing else in the crate may write to stdout during a
serve, so this helper is the stdout-purity enforcement point (C-005).