+ * Use: The @key_merge@ function reads keys from a file, and inserts
+ * them into the keyring.
+ *
+ * The @key_mergeline@ function reads a key from a single input
+ * line (which may, but need not, have a final newline), and
+ * adds it to the keyring.
+ *
+ * The @key_mergeline@ function is intended to help with
+ * interfacing Catacomb to runtimes which don't use C's @stdio@
+ * streams, rather than as a general-purpose service, though if
+ * it turns out to be useful in other ways then so much the
+ * better.