--- a/src/hotspot/share/runtime/os.hpp	Sun Jan 13 17:33:26 2019 +0100
+++ b/src/hotspot/share/runtime/os.hpp	Sun Jan 13 16:54:01 2019 -0500
@@ -539,9 +539,8 @@
 
   //File i/o operations
 
-  static size_t read(int fd, void *buf, unsigned int nBytes);
-  static size_t read_at(int fd, void *buf, unsigned int nBytes, jlong offset);
-  static size_t restartable_read(int fd, void *buf, unsigned int nBytes);
+  static ssize_t read(int fd, void *buf, unsigned int nBytes);
+  static ssize_t read_at(int fd, void *buf, unsigned int nBytes, jlong offset);
   static size_t write(int fd, const void *buf, unsigned int nBytes);
 
   // Reading directories.