--- /dev/null
+#include <stdio.h>
+#include <string.h>
+#include "config.h"
+
+/**
+ * daemon_with_notify - daemonize a process, can wait for child to signal readiness
+ *
+ * Daemons should detach themselves thoroughly from the process which launched
+ * them, and not prevent any filesystems from being unmounted. daemonize()
+ * helps with the process.
+ *
+ * Daemon-with-notify is different in that the child can send a SIGUSR1 to
+ * the parent to indicate it has started (e.g. after memory allocation and
+ * other things that may fail) so that the parent can return a success or
+ * failing exit code and init scripts can pick this up easily.
+ *
+ * Example:
+ * #include <ccan/daemon_with_notify/daemon_with_notify.h>
+ * #include <ccan/str/str.h>
+ * #include <err.h>
+ * #include <unistd.h>
+ * #include <stdlib.h>
+ *
+ * static void usage(const char *name)
+ * {
+ * errx(1, "Usage: %s [--daemonize]\n", name);
+ * }
+ *
+ * // Wait for a minute, possibly as a daemon.
+ * int main(int argc, char *argv[])
+ * {
+ * if (argc != 1) {
+ * if (argc == 2 && streq(argv[1], "--daemonize")) {
+ * if (!daemonize(1, 1, 1))
+ * err(1, "Failed to become daemon");
+ * } else
+ * usage(argv[1]);
+ * }
+ * sleep(10); // do some init here
+ * daemon_is_ready();
+ * sleep(20); // will be done in child, detached from parent
+ * exit(0);
+ * }
+ *
+ * License: BSD
+ * Author: Stewart Smith <stewart@flamingspork.com>
+ */
+int main(int argc, char *argv[])
+{
+ if (argc != 2)
+ return 1;
+
+ if (strcmp(argv[1], "depends") == 0) {
+ return 0;
+ }
+
+ if (strcmp(argv[1], "libs") == 0) {
+ return 0;
+ }
+
+ return 1;
+}
+