-static void vox_open P_ ((struct sound_device *));
-static void vox_configure P_ ((struct sound_device *));
-static void vox_close P_ ((struct sound_device *sd));
-static void vox_choose_format P_ ((struct sound_device *, struct sound *));
-static int vox_init P_ ((struct sound_device *));
-static void vox_write P_ ((struct sound_device *, const char *, int));
-static void find_sound_type P_ ((struct sound *));
-static u_int32_t le2hl P_ ((u_int32_t));
-static u_int16_t le2hs P_ ((u_int16_t));
-static u_int32_t be2hl P_ ((u_int32_t));
-static int wav_init P_ ((struct sound *));
-static void wav_play P_ ((struct sound *, struct sound_device *));
-static int au_init P_ ((struct sound *));
-static void au_play P_ ((struct sound *, struct sound_device *));
+static void vox_open (struct sound_device *);
+static void vox_configure (struct sound_device *);
+static void vox_close (struct sound_device *sd);
+static void vox_choose_format (struct sound_device *, struct sound *);
+static int vox_init (struct sound_device *);
+static void vox_write (struct sound_device *, const char *, ptrdiff_t);
+static void find_sound_type (struct sound *);
+static u_int32_t le2hl (u_int32_t);
+static u_int16_t le2hs (u_int16_t);
+static u_int32_t be2hl (u_int32_t);
+static int wav_init (struct sound *);
+static void wav_play (struct sound *, struct sound_device *);
+static int au_init (struct sound *);
+static void au_play (struct sound *, struct sound_device *);