Add --detach. Add multi-pass flag parsing that lets us get things in the right order.

adsbus/stdinout.c

@@ -0,0 +1,37 @@
+#include <assert.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+#include "flow.h"
+#include "opts.h"
+#include "receive.h"
+#include "send.h"
+
+#include "stdinout.h"
+
+static opts_group stdinout_opts;
+
+static bool stdinout_stdin(const char __attribute__((unused)) *arg) {
+	int fd = fcntl(STDIN_FILENO, F_DUPFD_CLOEXEC, 0);
+	assert(fd >= 0);
+	return flow_new_send_hello(fd, receive_flow, NULL, NULL);
+}
+
+static bool stdinout_stdout(const char *arg) {
+	struct serializer *serializer = send_get_serializer(arg);
+	if (!serializer) {
+		return false;
+	}
+	int fd = fcntl(STDOUT_FILENO, F_DUPFD_CLOEXEC, 0);
+	assert(fd >= 0);
+	return flow_new_send_hello(fd, send_flow, serializer, NULL);
+}
+
+void stdinout_opts_add() {
+	opts_add("stdin", NULL, stdinout_stdin, stdinout_opts);
+	opts_add("stdout", "FORMAT", stdinout_stdout, stdinout_opts);
+}
+
+void stdinout_init() {
+	opts_call(stdinout_opts);
+}