-extern mexp_h *mexp_spawnv (const char *file, char **argv);
-extern mexp_h *mexp_spawnl (const char *file, const char *arg, ...);
+extern mexp_h *mexp_spawnvf (unsigned flags, const char *file, char **argv);
+extern mexp_h *mexp_spawnlf (unsigned flags, const char *file, const char *arg, ...);
+#define mexp_spawnv(file,argv) mexp_spawnvf (0, (file), (argv))
+#define mexp_spawnl(file,...) mexp_spawnlf (0, (file), __VA_ARGS__)
+
+#define MEXP_SPAWN_KEEP_SIGNALS 1
+#define MEXP_SPAWN_KEEP_FDS 2
+#define MEXP_SPAWN_COOKED_MODE 4
+#define MEXP_SPAWN_RAW_MODE 0