diff --git a/gdk-pixbuf/ChangeLog b/gdk-pixbuf/ChangeLog
index e98ffe8c73..57ba7c401a 100644
--- a/gdk-pixbuf/ChangeLog
+++ b/gdk-pixbuf/ChangeLog
@@ -1,3 +1,7 @@
+1999-11-02 Elliot Lee <sopwith@redhat.com>
+	* src/gdk-pixbuf-loader.[ch], src/gdk-pixbuf-io.h: Make the arguments to the
+	write/load_increment operations const-correct.
+
 1999-11-02  Federico Mena Quintero  <federico@redhat.com>
 
 	* src/gnome-canvas-pixbuf.c (gnome_canvas_pixbuf_point):
diff --git a/gdk-pixbuf/gdk-pixbuf-io.h b/gdk-pixbuf/gdk-pixbuf-io.h
index 0e203b54cc..4706106a8b 100644
--- a/gdk-pixbuf/gdk-pixbuf-io.h
+++ b/gdk-pixbuf/gdk-pixbuf-io.h
@@ -51,7 +51,7 @@ struct _GdkPixbufModule {
         /* Incremental loading */
         gpointer   (* begin_load)    (ModulePreparedNotifyFunc func, gpointer user_data);
         void       (* stop_load)     (gpointer context);
-        gboolean   (* load_increment)(gpointer context, guchar *buf, guint size);
+        gboolean   (* load_increment)(gpointer context, const gchar *buf, guint size);
 };
 
 
diff --git a/gdk-pixbuf/gdk-pixbuf-loader.c b/gdk-pixbuf/gdk-pixbuf-loader.c
index 525345d57f..c62d325f89 100644
--- a/gdk-pixbuf/gdk-pixbuf-loader.c
+++ b/gdk-pixbuf/gdk-pixbuf-loader.c
@@ -273,7 +273,7 @@ gdk_pixbuf_loader_load_module(GdkPixbufLoader *loader)
 }
 
 static int
-gdk_pixbuf_loader_eat_header_write (GdkPixbufLoader *loader, guchar *buf, size_t count)
+gdk_pixbuf_loader_eat_header_write (GdkPixbufLoader *loader, const gchar *buf, size_t count)
 {
 	int nbytes;
 	GdkPixbufLoaderPrivate *priv = loader->private;
@@ -303,7 +303,7 @@ gdk_pixbuf_loader_eat_header_write (GdkPixbufLoader *loader, guchar *buf, size_t
  * cannot parse the buf.
  **/
 gboolean
-gdk_pixbuf_loader_write (GdkPixbufLoader *loader, guchar *buf, size_t count)
+gdk_pixbuf_loader_write (GdkPixbufLoader *loader, const gchar *buf, size_t count)
 {
 	GdkPixbufLoaderPrivate *priv;
 
diff --git a/gdk-pixbuf/gdk-pixbuf-loader.h b/gdk-pixbuf/gdk-pixbuf-loader.h
index 3e947ec054..76997a117d 100644
--- a/gdk-pixbuf/gdk-pixbuf-loader.h
+++ b/gdk-pixbuf/gdk-pixbuf-loader.h
@@ -68,7 +68,7 @@ struct _GdkPixbufLoaderClass {
 
 GtkType gdk_pixbuf_loader_get_type (void);
 GdkPixbufLoader *gdk_pixbuf_loader_new (void);
-gboolean gdk_pixbuf_loader_write (GdkPixbufLoader *loader, guchar *buf, size_t count);
+gboolean gdk_pixbuf_loader_write (GdkPixbufLoader *loader, const gchar *buf, size_t count);
 GdkPixbuf *gdk_pixbuf_loader_get_pixbuf (GdkPixbufLoader *loader);
 void gdk_pixbuf_loader_close (GdkPixbufLoader *loader);
 
diff --git a/gtk/gdk-pixbuf-loader.c b/gtk/gdk-pixbuf-loader.c
index 525345d57f..c62d325f89 100644
--- a/gtk/gdk-pixbuf-loader.c
+++ b/gtk/gdk-pixbuf-loader.c
@@ -273,7 +273,7 @@ gdk_pixbuf_loader_load_module(GdkPixbufLoader *loader)
 }
 
 static int
-gdk_pixbuf_loader_eat_header_write (GdkPixbufLoader *loader, guchar *buf, size_t count)
+gdk_pixbuf_loader_eat_header_write (GdkPixbufLoader *loader, const gchar *buf, size_t count)
 {
 	int nbytes;
 	GdkPixbufLoaderPrivate *priv = loader->private;
@@ -303,7 +303,7 @@ gdk_pixbuf_loader_eat_header_write (GdkPixbufLoader *loader, guchar *buf, size_t
  * cannot parse the buf.
  **/
 gboolean
-gdk_pixbuf_loader_write (GdkPixbufLoader *loader, guchar *buf, size_t count)
+gdk_pixbuf_loader_write (GdkPixbufLoader *loader, const gchar *buf, size_t count)
 {
 	GdkPixbufLoaderPrivate *priv;
 
diff --git a/gtk/gdk-pixbuf-loader.h b/gtk/gdk-pixbuf-loader.h
index 3e947ec054..76997a117d 100644
--- a/gtk/gdk-pixbuf-loader.h
+++ b/gtk/gdk-pixbuf-loader.h
@@ -68,7 +68,7 @@ struct _GdkPixbufLoaderClass {
 
 GtkType gdk_pixbuf_loader_get_type (void);
 GdkPixbufLoader *gdk_pixbuf_loader_new (void);
-gboolean gdk_pixbuf_loader_write (GdkPixbufLoader *loader, guchar *buf, size_t count);
+gboolean gdk_pixbuf_loader_write (GdkPixbufLoader *loader, const gchar *buf, size_t count);
 GdkPixbuf *gdk_pixbuf_loader_get_pixbuf (GdkPixbufLoader *loader);
 void gdk_pixbuf_loader_close (GdkPixbufLoader *loader);