X-Git-Url: http://nitlanguage.org

diff --git a/src/interpreter/primitive_types.nit b/src/interpreter/primitive_types.nit
index 496840d..ba058c1 100644
--- a/src/interpreter/primitive_types.nit
+++ b/src/interpreter/primitive_types.nit
@@ -14,8 +14,8 @@
 # underlying implementation and that the services are semantically correct.
 module primitive_types
 
-intrude import standard::file
-intrude import standard::text::flat
+intrude import core::file
+intrude import core::text::flat
 
 # Wrapper for `NativeFile`
 class PrimitiveNativeFile
@@ -47,16 +47,16 @@ class PrimitiveNativeFile
 		return false
 	end
 
-	fun io_read(buf: NativeString, len: Int): Int do
+	fun io_read(buf: CString, len: Int): Int do
 		if file isa FileStream then return file.as(FileStream)._file.io_read(buf, len)
 		var str = file.as(Reader).read(len)
 		str.to_cstring.copy_to(buf, str.length, 0, 0)
 		return str.length
 	end
 
-	fun io_write(buf: NativeString, len: Int): Int do
-		if file isa FileStream then return file.as(FileStream)._file.io_write(buf, len)
-		file.as(Writer).write(buf.to_s_with_length(len))
+	fun io_write(buf: CString, from, len: Int): Int do
+		if file isa FileStream then return file.as(FileStream)._file.io_write(buf, from, len)
+		file.as(Writer).write(buf.to_s_unsafe(len, copy=false).substring_from(from))
 		return len
 	end