diff --git a/libvips/foreign/dzsave.c b/libvips/foreign/dzsave.c
index a1ab7067..49505e39 100644
--- a/libvips/foreign/dzsave.c
+++ b/libvips/foreign/dzsave.c
@@ -1030,20 +1030,23 @@ char *
 build_scan_properties( VipsImage *image )
 {
 	VipsDbuf dbuf;
-	GTimeVal now;
+	GDateTime *now;
 	char *date;
 	int i;
 
+	now = g_date_time_new_now_local();
+	date = g_date_time_format_iso8601( now );
+	g_date_time_unref( now );
+
 	vips_dbuf_init( &dbuf );
 
-	g_get_current_time( &now );
-	date = g_time_val_to_iso8601( &now );
 	vips_dbuf_writef( &dbuf, "<?xml version=\"1.0\"?>\n" ); 
 	vips_dbuf_writef( &dbuf, "<image xmlns=\"http://www.pathozoom.com/szi\""
 		" date=\"%s\" version=\"1.0\">\n", date );
-	g_free( date ); 
 	vips_dbuf_writef( &dbuf, "  <properties>\n" );  
 
+	g_free( date ); 
+
 	for( i = 0; i < VIPS_NUMBER( scan_property_names ); i++ )
 		build_scan_property( &dbuf, image,
 			scan_property_names[i][0],
diff --git a/libvips/foreign/jpeg2vips.c b/libvips/foreign/jpeg2vips.c
index e595e1c0..91797308 100644
--- a/libvips/foreign/jpeg2vips.c
+++ b/libvips/foreign/jpeg2vips.c
@@ -558,7 +558,8 @@ read_jpeg_header( ReadJpeg *jpeg, VipsImage *out )
 		interpretation,
 		xres, yres );
 
-	VIPS_SETSTR( out->filename, VIPS_STREAM( jpeg->input )->filename );
+	VIPS_SETSTR( out->filename, 
+		vips_stream_filename( VIPS_STREAM( jpeg->input ) ) );
 
 	vips_image_pipelinev( out, VIPS_DEMAND_STYLE_FATSTRIP, NULL );
 
@@ -743,11 +744,6 @@ read_jpeg_generate( VipsRegion *or,
 		g_thread_self(), r->top, r->height );
 #endif /*DEBUG_VERBOSE*/
 
-	/* In pixel decode mode.
-	 */
-	if( vips_streami_decode( jpeg->input ) )
-		return( -1 );
-
 	VIPS_GATE_START( "read_jpeg_generate: work" );
 
 	/* We're inside a tilecache where tiles are the full image width, so
@@ -953,8 +949,6 @@ vips__jpeg_read( ReadJpeg *jpeg, VipsImage *out, gboolean header_only )
 			 */
 			vips_autorot_remove_angle( out ); 
 		}
-
-		vips_streami_minimise( jpeg->input );
 	}
 	else {
 		if( read_jpeg_image( jpeg, out ) )
@@ -976,10 +970,9 @@ vips__jpeg_read_stream( VipsStreami *input, VipsImage *out,
 	if( setjmp( jpeg->eman.jmp ) ) 
 		return( -1 );
 
-	if( readjpeg_open_input( jpeg ) )
-                return( -1 );
-
-	if( vips__jpeg_read( jpeg, out, header_only ) ) 
+	if( readjpeg_open_input( jpeg ) ||
+		vips__jpeg_read( jpeg, out, header_only ) ||
+		vips_streami_decode( jpeg->input ) )
 		return( -1 );
 
 	return( 0 );
diff --git a/libvips/foreign/tiff2vips.c b/libvips/foreign/tiff2vips.c
index d628e1de..e3f72fa8 100644
--- a/libvips/foreign/tiff2vips.c
+++ b/libvips/foreign/tiff2vips.c
@@ -534,7 +534,8 @@ rtiff_new( VipsStreami *input, VipsImage *out,
 	g_signal_connect( out, "minimise",
 		G_CALLBACK( rtiff_minimise_cb ), rtiff ); 
 
-	if( rtiff->page < 0 || rtiff->page > 1000000 ) {
+	if( rtiff->page < 0 || 
+		rtiff->page > 1000000 ) {
 		vips_error( "tiff2vips", _( "bad page number %d" ),
 			rtiff->page );
 		return( NULL );
@@ -1367,6 +1368,9 @@ rtiff_set_header( Rtiff *rtiff, VipsImage *out )
 	out->Xsize = rtiff->header.width;
 	out->Ysize = rtiff->header.height * rtiff->n;
 
+	VIPS_SETSTR( out->filename, 
+		vips_stream_filename( VIPS_STREAM( rtiff->input ) ) );
+
 	if( rtiff->n > 1 ) 
 		vips_image_set_int( out, 
 			VIPS_META_PAGE_HEIGHT, rtiff->header.height );
@@ -1534,9 +1538,6 @@ rtiff_fill_region( VipsRegion *out,
 
 	int x, y, z;
 
-	if( vips_streami_unminimise( rtiff->input ) ) 
-		return( -1 );
-
 	/* Special case: we are filling a single tile exactly sized to match
 	 * the tiff tile and we have no repacking to do for this format.
 	 */
@@ -1863,9 +1864,6 @@ rtiff_stripwise_generate( VipsRegion *or,
 	g_assert( r->height == 
 		VIPS_MIN( read_height, or->im->Ysize - r->top ) ); 
 
-	if( vips_streami_unminimise( rtiff->input ) ) 
-		return( -1 );
-
 	/* And check that y_pos is correct. It should be, since we are inside
 	 * a vips_sequential().
 	 */
diff --git a/libvips/foreign/tiffload.c b/libvips/foreign/tiffload.c
index 45546fa4..78c0fd36 100644
--- a/libvips/foreign/tiffload.c
+++ b/libvips/foreign/tiffload.c
@@ -198,8 +198,6 @@ vips_foreign_load_tiff_file_header( VipsForeignLoad *load )
 	}
 	VIPS_UNREF( input );
 
-	VIPS_SETSTR( load->out->filename, file->filename );
-
 	return( 0 );
 }
 
diff --git a/libvips/foreign/vipspng.c b/libvips/foreign/vipspng.c
index b43eabfd..0b3e7992 100644
--- a/libvips/foreign/vipspng.c
+++ b/libvips/foreign/vipspng.c
@@ -481,7 +481,8 @@ png2vips_header( Read *read, VipsImage *out )
 		VIPS_CODING_NONE, interpretation, 
 		Xres, Yres );
 
-	VIPS_SETSTR( out->filename, VIPS_STREAM( read->input )->filename );
+	VIPS_SETSTR( out->filename, 
+		vips_stream_filename( VIPS_STREAM( read->input ) ) );
 
 	/* Uninterlaced images will be read in seq mode. Interlaced images are
 	 * read via a huge memory buffer.
@@ -621,11 +622,6 @@ png2vips_generate( VipsRegion *or,
 		return( -1 );
 	}
 
-	/* In pixel decode mode.
-	 */
-	if( vips_streami_decode( read->input ) )
-		return( -1 );
-
 	for( y = 0; y < r->height; y++ ) {
 		png_bytep q = (png_bytep) VIPS_REGION_ADDR( or, 0, r->top + y );
 
@@ -715,11 +711,10 @@ vips__png_header_stream( VipsStreami *input, VipsImage *out )
 	Read *read;
 
 	if( !(read = read_new( input, out, TRUE )) ||
-		png2vips_header( read, out ) ) 
+		png2vips_header( read, out ) || 
+		vips_streami_decode( input ) )
 		return( -1 );
 
-	vips_streami_minimise( input );
-
 	return( 0 );
 }
 
@@ -729,8 +724,9 @@ vips__png_read_stream( VipsStreami *input, VipsImage *out, gboolean fail )
 	Read *read;
 
 	if( !(read = read_new( input, out, fail )) ||
-		png2vips_image( read, out ) )
-		return( -1 ); 
+		png2vips_image( read, out ) ||
+		vips_streami_decode( input ) )
+		return( -1 );
 
 	return( 0 );
 }
diff --git a/libvips/include/vips/stream.h b/libvips/include/vips/stream.h
index abd80b0f..2fd08af4 100644
--- a/libvips/include/vips/stream.h
+++ b/libvips/include/vips/stream.h
@@ -88,7 +88,8 @@ GType vips_stream_get_type( void );
 
 int vips_stream_open( VipsStream *stream );
 int vips_stream_close( VipsStream *stream );
-const char *vips_stream_name( VipsStream *stream );
+const char *vips_stream_filename( VipsStream *stream );
+const char *vips_stream_nick( VipsStream *stream );
 
 #define VIPS_TYPE_STREAMI (vips_streami_get_type())
 #define VIPS_STREAMI( obj ) \
@@ -204,13 +205,13 @@ VipsStreami *vips_streami_new_from_blob( VipsBlob *blob );
 VipsStreami *vips_streami_new_from_memory( const void *data, size_t size );
 VipsStreami *vips_streami_new_from_options( const char *options );
 
+void vips_streami_minimise( VipsStreami *streami );
+int vips_streami_unminimise( VipsStreami *streami );
+int vips_streami_decode( VipsStreami *streami );
 ssize_t vips_streami_read( VipsStreami *streami, void *data, size_t length );
 const void *vips_streami_map( VipsStreami *streami, size_t *length );
 gint64 vips_streami_seek( VipsStreami *streami, gint64 offset, int whence );
 int vips_streami_rewind( VipsStreami *streami );
-void vips_streami_minimise( VipsStreami *streami );
-int vips_streami_unminimise( VipsStreami *streami );
-int vips_streami_decode( VipsStreami *streami );
 unsigned char *vips_streami_sniff( VipsStreami *streami, size_t length );
 gint64 vips_streami_size( VipsStreami *streami ); 
 
diff --git a/libvips/iofuncs/stream.c b/libvips/iofuncs/stream.c
index 5e2432b4..f048be6d 100644
--- a/libvips/iofuncs/stream.c
+++ b/libvips/iofuncs/stream.c
@@ -143,10 +143,15 @@ vips_stream_init( VipsStream *stream )
 }
 
 const char *
-vips_stream_name( VipsStream *stream )
+vips_stream_filename( VipsStream *stream )
+{
+	return( stream->filename );
+}
+
+const char *
+vips_stream_nick( VipsStream *stream )
 {
 	return( stream->filename ?
 		stream->filename :
 		VIPS_OBJECT( stream )->nickname );
 }
-
diff --git a/libvips/iofuncs/streami.c b/libvips/iofuncs/streami.c
index 7d28ab4b..c2331b2f 100644
--- a/libvips/iofuncs/streami.c
+++ b/libvips/iofuncs/streami.c
@@ -34,15 +34,11 @@
 /* TODO
  *
  * - filename encoding
- * - move fds in here
- * - add vips_stream_nick() to make stream nickname
+ * - something to stop unbounded streams filling memory
  * - gaussblur is missing the vector path again argh
  * - can we map and then close the fd? how about on Windows?
- * - are we detecting EOF correctly? what about interrupted reads? perhaps 
- *   we should check errno as well
- * - need to be able to set is_pipe via constructor
- * - need open()/close() as vfuncs?
- * - make a subclass that lets you set vfuncs as params
+ * - make a subclass that lets you set vfuncs as params, inc. close(),
+ *   is_pipe etc.
  */
 
 /*
@@ -94,6 +90,7 @@
 
 G_DEFINE_TYPE( VipsStreami, vips_streami, VIPS_TYPE_STREAM );
 
+#ifdef VIPS_DEBUG
 static void
 vips_streami_sanity( VipsStreami *streami )
 {
@@ -182,6 +179,13 @@ vips_streami_sanity( VipsStreami *streami )
 			 VIPS_STREAM( streami )->descriptor) );
 	}
 }
+#endif /*VIPS_DEBUG*/
+
+#ifdef VIPS_DEBUG
+#define SANITY( S ) vips_streami_sanity( S )
+#else /*!VIPS_DEBUG*/
+#define SANITY( S )
+#endif /*VIPS_DEBUG*/
 
 static void
 vips_streami_finalize( GObject *gobject )
@@ -213,7 +217,7 @@ vips_streami_build( VipsObject *object )
 
 	if( vips_object_argument_isset( object, "filename" ) &&
 		vips_object_argument_isset( object, "descriptor" ) ) { 
-		vips_error( vips_stream_name( stream ), 
+		vips_error( vips_stream_nick( stream ), 
 			"%s", _( "don't set 'filename' and 'descriptor'" ) ); 
 		return( -1 ); 
 	}
@@ -269,9 +273,16 @@ vips_streami_read_real( VipsStreami *streami, void *data, size_t length )
 {
 	VipsStream *stream = VIPS_STREAM( streami );
 
+	ssize_t bytes_read;
+
 	VIPS_DEBUG_MSG( "vips_streami_read_real:\n" );
 
-	return( read( stream->descriptor, data, length ) );
+	do { 
+		bytes_read = read( stream->descriptor, data, length );
+	} while( bytes_read < 0 && errno == EINTR );
+
+	return( bytes_read );
+
 }
 
 static gint64
@@ -354,7 +365,7 @@ vips_streami_new_from_descriptor( int descriptor )
 		return( NULL );
 	}
 
-	vips_streami_sanity( streami );
+	SANITY( streami );
 
 	return( streami ); 
 }
@@ -384,7 +395,7 @@ vips_streami_new_from_filename( const char *filename )
 		return( NULL );
 	}
 
-	vips_streami_sanity( streami );
+	SANITY( streami );
 
 	return( streami ); 
 }
@@ -413,7 +424,7 @@ vips_streami_new_from_blob( VipsBlob *blob )
 		return( NULL );
 	}
 
-	vips_streami_sanity( streami );
+	SANITY( streami );
 
 	return( streami ); 
 }
@@ -446,7 +457,7 @@ vips_streami_new_from_memory( const void *data, size_t length )
 
 	vips_area_unref( VIPS_AREA( blob ) );
 
-	vips_streami_sanity( streami );
+	SANITY( streami );
 
 	return( streami ); 
 }
@@ -474,11 +485,123 @@ vips_streami_new_from_options( const char *options )
 		return( NULL );
 	}
 
-	vips_streami_sanity( streami );
+	SANITY( streami );
 
 	return( streami ); 
 }
 
+/**
+ * vips_streami_minimise:
+ * @streami: input stream to operate on
+ *
+ * Minimise the stream. As many stream resources as can be safely removed are
+ * removed. Use vips_streami_unminimise() to restore the stream if you wish to
+ * use it again.
+ *
+ * Loaders should call this in response to the minimise signal on their output
+ * image.
+ *
+ * Returns: 0 on success, or -1 on error.
+ */
+void
+vips_streami_minimise( VipsStreami *streami )
+{
+	VipsStream *stream = VIPS_STREAM( streami );
+
+	VIPS_DEBUG_MSG( "vips_streami_minimise:\n" );
+
+	SANITY( streami );
+
+	if( stream->filename &&
+		stream->descriptor != -1 &&
+		stream->tracked_descriptor == stream->descriptor &&
+		!streami->is_pipe ) {
+		VIPS_DEBUG_MSG( "    tracked_close()\n" );
+		vips_tracked_close( stream->tracked_descriptor );
+		stream->tracked_descriptor = -1;
+		stream->descriptor = -1;
+	}
+
+	SANITY( streami );
+}
+
+/**
+ * vips_streami_unminimise:
+ * @streami: input stream to operate on
+ *
+ * Restore the stream after minimisation. This is called at the start 
+ * of every stream method, so loaders should not usually need this.
+ *
+ * See also: vips_streami_minimise().
+ *
+ * Returns: 0 on success, or -1 on error.
+ */
+int
+vips_streami_unminimise( VipsStreami *streami )
+{
+	VipsStream *stream = VIPS_STREAM( streami );
+
+	VIPS_DEBUG_MSG( "vips_streami_unminimise:\n" );
+
+	if( stream->descriptor == -1 &&
+		stream->tracked_descriptor == -1 &&
+		stream->filename ) {
+		int fd;
+
+		if( (fd = vips_tracked_open( stream->filename, 
+			MODE_READ )) == -1 ) 
+			return( -1 ); 
+
+		stream->tracked_descriptor = fd;
+		stream->descriptor = fd;
+
+		VIPS_DEBUG_MSG( "vips_streami_unminimise: "
+			"restoring read position %zd\n", 
+			streami->read_position );
+		if( vips__seek( stream->descriptor, 
+			streami->read_position, SEEK_SET ) == -1 )
+			return( -1 );
+	}
+
+	return( 0 );
+}
+
+/**
+ * vips_streami_decode:
+ * @streami: input stream to operate on
+ *
+ * Signal the end of header read and the start of the pixel decode phase. 
+ * After this, you can no longer seek on this stream.
+ *
+ * Loaders should call this at the end of header read.
+ *
+ * See also: vips_streami_unminimise().
+ *
+ * Returns: 0 on success, -1 on error.
+ */
+int
+vips_streami_decode( VipsStreami *streami )
+{
+	VIPS_DEBUG_MSG( "vips_streami_decode:\n" );
+
+	SANITY( streami );
+
+	/* We have finished reading the header. We can discard the header bytes
+	 * we saved.
+	 */
+	if( !streami->decode ) {
+		streami->decode = TRUE;
+		VIPS_FREEF( g_byte_array_unref, streami->header_bytes ); 
+		VIPS_FREEF( g_byte_array_unref, streami->sniff ); 
+	}
+
+	vips_streami_minimise( streami );
+
+	SANITY( streami );
+
+	return( 0 );
+}
+
 /**
  * vips_streami_read:
  * @streami: input stream to operate on
@@ -502,7 +625,10 @@ vips_streami_read( VipsStreami *streami, void *buffer, size_t length )
 
 	VIPS_DEBUG_MSG( "vips_streami_read:\n" );
 
-	vips_streami_sanity( streami );
+	SANITY( streami );
+
+	if( vips_streami_unminimise( streami ) )
+		return( -1 );
 
 	bytes_read = 0;
 
@@ -551,7 +677,7 @@ vips_streami_read( VipsStreami *streami, void *buffer, size_t length )
 			VIPS_DEBUG_MSG( "    %zd bytes from read()\n", n );
 			if( n == -1 ) {
 				vips_error_system( errno, 
-					vips_stream_name( 
+					vips_stream_nick( 
 						VIPS_STREAM( streami ) ), 
 					"%s", _( "read error" ) ); 
 				return( -1 );
@@ -574,7 +700,7 @@ vips_streami_read( VipsStreami *streami, void *buffer, size_t length )
 
 	VIPS_DEBUG_MSG( "    %zd bytes total\n", bytes_read );
 
-	vips_streami_sanity( streami );
+	SANITY( streami );
 
 	return( bytes_read );
 }
@@ -588,7 +714,8 @@ vips_streami_pipe_read_to_position( VipsStreami *streami, gint64 target )
 	gint64 old_read_position;
 	unsigned char buffer[4096];
 
-	VIPS_DEBUG_MSG( "vips_streami_pipe_read_position:\n" );
+	VIPS_DEBUG_MSG( "vips_streami_pipe_read_position: %" G_GINT64_FORMAT 
+		"\n", target );
 
 	g_assert( !streami->decode );
 	g_assert( streami->header_bytes );
@@ -596,14 +723,15 @@ vips_streami_pipe_read_to_position( VipsStreami *streami, gint64 target )
 	if( target < 0 ||
 		(streami->length != -1 && 
 		 target > streami->length) ) {
-		vips_error( vips_stream_name( VIPS_STREAM( streami ) ), 
+		vips_error( vips_stream_nick( VIPS_STREAM( streami ) ), 
 			_( "bad read to %" G_GINT64_FORMAT ), target );
 		return( -1 );
 	}
 
 	old_read_position = streami->read_position;
 
-	/* TODO ... add something to prevent unbounded streams filling memory.
+	/* TODO ... add something to prevent unbounded streams filling memory
+	 * if target == -1.
 	 */
 	while( target == -1 ||
 		streami->read_position < target ) {
@@ -688,7 +816,10 @@ vips_streami_map( VipsStreami *streami, size_t *length_out )
 
 	VIPS_DEBUG_MSG( "vips_streami_map:\n" );
 
-	vips_streami_sanity( streami );
+	SANITY( streami );
+
+	if( vips_streami_unminimise( streami ) )
+		return( NULL );
 
 	/* Pipes need to be converted to memory streams.
 	 */
@@ -709,7 +840,7 @@ vips_streami_map( VipsStreami *streami, size_t *length_out )
 	if( length_out )
 		*length_out = streami->length;
 
-	vips_streami_sanity( streami );
+	SANITY( streami );
 
 	return( streami->data );
 }
@@ -735,7 +866,10 @@ vips_streami_seek( VipsStreami *streami, gint64 offset, int whence )
 	VIPS_DEBUG_MSG( "vips_streami_seek: offset = %" G_GINT64_FORMAT 
 		", whence = %d\n", offset, whence );
 
-	vips_streami_sanity( streami );
+	SANITY( streami );
+
+	if( vips_streami_unminimise( streami ) )
+		return( -1 );
 
 	if( streami->data ) {
 		switch( whence ) {
@@ -752,7 +886,7 @@ vips_streami_seek( VipsStreami *streami, gint64 offset, int whence )
 			break;
 
 		default:
-			vips_error( vips_stream_name( VIPS_STREAM( streami ) ), 
+			vips_error( vips_stream_nick( VIPS_STREAM( streami ) ), 
 				"%s", _( "bad 'whence'" ) );
 			return( -1 );
 			break;
@@ -780,7 +914,7 @@ vips_streami_seek( VipsStreami *streami, gint64 offset, int whence )
 			break;
 
 		default:
-			vips_error( vips_stream_name( VIPS_STREAM( streami ) ), 
+			vips_error( vips_stream_nick( VIPS_STREAM( streami ) ), 
 				"%s", _( "bad 'whence'" ) );
 			return( -1 );
 			break;
@@ -799,14 +933,14 @@ vips_streami_seek( VipsStreami *streami, gint64 offset, int whence )
 	if( new_pos < 0 ||
 		(streami->length != -1 && 
 		 new_pos > streami->length) ) {
-		vips_error( vips_stream_name( VIPS_STREAM( streami ) ), 
+		vips_error( vips_stream_nick( VIPS_STREAM( streami ) ), 
 			_( "bad seek to %" G_GINT64_FORMAT ), new_pos );
                 return( -1 );
 	}
 
 	streami->read_position = new_pos;
 
-	vips_streami_sanity( streami );
+	SANITY( streami );
 
 	VIPS_DEBUG_MSG( "    new_pos = %" G_GINT64_FORMAT "\n", new_pos );
 
@@ -827,82 +961,12 @@ vips_streami_rewind( VipsStreami *streami )
 {
 	VIPS_DEBUG_MSG( "vips_streami_rewind:\n" );
 
-	vips_streami_sanity( streami );
+	SANITY( streami );
 
 	if( vips_streami_seek( streami, 0, SEEK_SET ) != 0 )
 		return( -1 );
 
-	vips_streami_sanity( streami );
-
-	return( 0 );
-}
-
-/**
- * vips_streami_minimise:
- * @streami: input stream to operate on
- *
- * Minimise the stream. As many stream resources as can be safely removed are
- * removed. Use vips_streami_unminimise() to restore the stream if you wish to
- * use it again.
- *
- * Returns: 0 on success, or -1 on error.
- */
-void
-vips_streami_minimise( VipsStreami *streami )
-{
-	VipsStream *stream = VIPS_STREAM( streami );
-
-	VIPS_DEBUG_MSG( "vips_streami_minimise:\n" );
-
-	vips_streami_sanity( streami );
-
-	if( stream->filename &&
-		stream->descriptor != -1 &&
-		stream->tracked_descriptor == stream->descriptor &&
-		!streami->is_pipe ) {
-		VIPS_DEBUG_MSG( "    tracked_close()\n" );
-		vips_tracked_close( stream->tracked_descriptor );
-		stream->tracked_descriptor = -1;
-		stream->descriptor = -1;
-	}
-
-	vips_streami_sanity( streami );
-}
-
-/**
- * vips_streami_unminimise:
- * @streami: input stream to operate on
- *
- * Restore the stream after minimisation.
- *
- * Returns: 0 on success, or -1 on error.
- */
-int
-vips_streami_unminimise( VipsStreami *streami )
-{
-	VipsStream *stream = VIPS_STREAM( streami );
-
-	VIPS_DEBUG_MSG( "vips_streami_unminimise:\n" );
-
-	if( stream->descriptor == -1 &&
-		stream->tracked_descriptor == -1 &&
-		stream->filename ) {
-		int fd;
-
-		if( (fd = vips_tracked_open( stream->filename, 
-			MODE_READ )) == -1 ) 
-			return( -1 ); 
-
-		stream->tracked_descriptor = fd;
-		stream->descriptor = fd;
-
-		VIPS_DEBUG_MSG( "vips_streami_unminimise: "
-			"restoring read position %zd\n", 
-			streami->read_position );
-		if( vips__seek( stream->descriptor, 
-			streami->read_position, SEEK_SET ) == -1 )
-			return( -1 );
-	}
+	SANITY( streami );
 
 	return( 0 );
 }
@@ -925,52 +989,17 @@ vips_streami_size( VipsStreami *streami )
 
 	VIPS_DEBUG_MSG( "vips_streami_size:\n" );
 
-	vips_streami_sanity( streami );
+	SANITY( streami );
 
 	read_position = vips_streami_seek( streami, 0, SEEK_CUR );
 	size = vips_streami_seek( streami, 0, SEEK_END );
 	vips_streami_seek( streami, read_position, SEEK_SET );
 
-	vips_streami_sanity( streami );
+	SANITY( streami );
 
 	return( size );
 }
 
-/**
- * vips_streami_decode:
- * @streami: input stream to operate on
- *
- * Signal the end of header read and the start of the pixel decode phase. After
- * this, you can no longer seek on this stream.
- *
- * Returns: 0 on success, -1 on error.
- */
-int
-vips_streami_decode( VipsStreami *streami )
-{
-	VIPS_DEBUG_MSG( "vips_streami_decode:\n" );
-
-	vips_streami_sanity( streami );
-
-	/* We have finished reading the header. We can discard the bytes we
-	 * saved.
-	 */
-	if( !streami->decode ) {
-		streami->decode = TRUE;
-		VIPS_FREEF( g_byte_array_unref, streami->header_bytes ); 
-		VIPS_FREEF( g_byte_array_unref, streami->sniff ); 
-	}
-
-	/* Make sure we are open, in case we've been minimised.
-	 */
-	if( vips_streami_unminimise( streami ) )
-		return( -1 );
-
-	vips_streami_sanity( streami );
-
-	return( 0 );
-}
-
 /**
  * vips_streami_sniff: 
  * @streami: sniff this stream
@@ -986,9 +1015,10 @@ vips_streami_sniff( VipsStreami *streami, size_t length )
 
 	VIPS_DEBUG_MSG( "vips_streami_sniff: %zd bytes\n", length );
 
-	vips_streami_sanity( streami );
+	SANITY( streami );
 
-	if( vips_streami_rewind( streami ) )
+	if( vips_streami_unminimise( streami ) ||
+		vips_streami_rewind( streami ) )
 		return( NULL );
 
 	g_byte_array_set_size( streami->sniff, length );
@@ -998,7 +1028,7 @@ vips_streami_sniff( VipsStreami *streami, size_t length )
 			n == 0 )
 			return( NULL );
 
-	vips_streami_sanity( streami );
+	SANITY( streami );
 
 	return( streami->sniff->data );
 }
diff --git a/libvips/iofuncs/streamo.c b/libvips/iofuncs/streamo.c
index bae97a1d..19226fb2 100644
--- a/libvips/iofuncs/streamo.c
+++ b/libvips/iofuncs/streamo.c
@@ -117,7 +117,7 @@ vips_streamo_build( VipsObject *object )
 
 	if( vips_object_argument_isset( object, "filename" ) &&
 		vips_object_argument_isset( object, "descriptor" ) ) { 
-		vips_error( vips_stream_name( stream ), 
+		vips_error( vips_stream_nick( stream ), 
 			"%s", _( "don't set 'filename' and 'descriptor'" ) ); 
 		return( -1 ); 
 	}
@@ -131,7 +131,7 @@ vips_streamo_build( VipsObject *object )
 		 */
 		if( (fd = vips_tracked_open( filename, 
 			MODE_WRITE, 0644 )) == -1 ) {
-			vips_error_system( errno, vips_stream_name( stream ), 
+			vips_error_system( errno, vips_stream_nick( stream ), 
 				"%s", _( "unable to open for write" ) ); 
 			return( -1 ); 
 		}
@@ -330,7 +330,7 @@ vips_streamo_write( VipsStreamo *streamo, const void *data, size_t length )
 		 */
 		if( n <= 0 ) {
 			vips_error_system( errno, 
-				vips_stream_name( VIPS_STREAM( streamo ) ),
+				vips_stream_nick( VIPS_STREAM( streamo ) ),
 				"%s", _( "write error" ) ); 
 			return( -1 ); 
 		}