diff --git a/format/desktop_entry/line.ha b/format/desktop_entry/line.ha
index 2eb27ee..c9fdaaf 100644
--- a/format/desktop_entry/line.ha
+++ b/format/desktop_entry/line.ha
@@ -1,3 +1,4 @@
+use fmt;
 use locale;
 use strings;
 
@@ -42,3 +43,19 @@ export fn entry_finish(entr: entry) void = {
 	free(entr.value);
 	locale::finish(entr.locale);
 };
+
+// Formats a [[line]] and writes it to an [[io::handle]].
+export fn fprint(output: io::handle, lin: line) (size | io::error) = match (lin) {
+case blank                 => yield fmt::fprintln(output, lin);
+case let lin: comment      => yield fmt::fprintf(output, "#{}\n", lin: string);
+case let lin: group_header => yield fmt::fprintf(output, "[{}]\n", lin: string);
+case let lin: entry =>
+	let wrote = fmt::print(lin.key)?;
+	if (!locale::equal(locale::c, lin.locale)) {
+		let localestr = locale::format(lin.locale);
+		defer free(localestr);
+		wrote += fmt::printf("[{}]", localestr)?;
+	};
+	wrote += fmt::printf("={}\n", lin.value)?;
+	yield wrote;
+};