Index: libs/regex/src/fileiter.cpp
===================================================================
--- libs/regex/src/fileiter.cpp	(revision 56576)
+++ libs/regex/src/fileiter.cpp	(working copy)
@@ -258,11 +258,23 @@
             *p = 0;
             *(reinterpret_cast<int*>(*node)) = 1;
          }
-         std::fseek(hfile, (node - _first) * buf_size, SEEK_SET);
-         if(node == _last - 1)
-            std::fread(*node + sizeof(int), _size % buf_size, 1, hfile);
+
+         std::size_t read_size = 0;
+         int read_pos = std::fseek(hfile, (node - _first) * buf_size, SEEK_SET);
+
+         if(0 == read_pos && node == _last - 1)
+            read_size = std::fread(*node + sizeof(int), _size % buf_size, 1, hfile);
          else
-            std::fread(*node + sizeof(int), buf_size, 1, hfile);
+            read_size = std::fread(*node + sizeof(int), buf_size, 1, hfile);
+
+#ifndef BOOST_NO_EXCEPTIONS
+         if (std::ferror(hfile))
+         {
+            throw std::runtime_error("Unable to read file.");
+         }
+#else
+         BOOST_REGEX_NOEH_ASSERT(0 == std::ferror(hfile));
+#endif
       }
       else
       {