diff --git a/doc/overview/posix.qbk b/doc/overview/posix.qbk
index 4d78cced..d7468ea8 100644
--- a/doc/overview/posix.qbk
+++ b/doc/overview/posix.qbk
@@ -75,7 +75,15 @@ target operating system. A program may test for the macro
 
 Boost.Asio includes classes added to permit synchronous and asynchronous read and
 write operations to be performed on POSIX file descriptors, such as pipes,
-standard input and output, and various devices (but /not/ regular files).
+standard input and output, and various devices.
+
+These classes also provide limited support for regular files. This support
+assumes that the underlying read and write operations provided by the operating
+system never fail with `EAGAIN` or `EWOULDBLOCK`. (This assumption normally
+holds for buffered file I/O.)  Synchronous and asynchronous read and write
+operations on file descriptors will succeed but the I/O will always be
+performed immediately. Wait operations, and operations involving
+`boost::asio::null_buffers`, are not portably supported.
 
 For example, to perform read and write operations on standard input
 and output, the following objects may be created:
diff --git a/include/boost/asio/detail/impl/epoll_reactor.ipp b/include/boost/asio/detail/impl/epoll_reactor.ipp
index b6b12a39..610ce31c 100644
--- a/include/boost/asio/detail/impl/epoll_reactor.ipp
+++ b/include/boost/asio/detail/impl/epoll_reactor.ipp
@@ -164,7 +164,18 @@ int epoll_reactor::register_descriptor(socket_type descriptor,
   ev.data.ptr = descriptor_data;
   int result = epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, descriptor, &ev);
   if (result != 0)
+  {
+    if (errno == EPERM)
+    {
+      // This file descriptor type is not supported by epoll. However, if it is
+      // a regular file then operations on it will not block. We will allow
+      // this descriptor to be used and fail later if an operation on it would
+      // otherwise require a trip through the reactor.
+      descriptor_data->registered_events_ = 0;
+      return 0;
+    }
     return errno;
+  }
 
   return 0;
 }
@@ -235,6 +246,13 @@ void epoll_reactor::start_op(int op_type, socket_type descriptor,
         return;
       }
 
+      if (descriptor_data->registered_events_ == 0)
+      {
+        op->ec_ = boost::asio::error::operation_not_supported;
+        io_service_.post_immediate_completion(op, is_continuation);
+        return;
+      }
+
       if (op_type == write_op)
       {
         if ((descriptor_data->registered_events_ & EPOLLOUT) == 0)
@@ -256,6 +274,12 @@ void epoll_reactor::start_op(int op_type, socket_type descriptor,
         }
       }
     }
+    else if (descriptor_data->registered_events_ == 0)
+    {
+      op->ec_ = boost::asio::error::operation_not_supported;
+      io_service_.post_immediate_completion(op, is_continuation);
+      return;
+    }
     else
     {
       if (op_type == write_op)
@@ -313,7 +337,7 @@ void epoll_reactor::deregister_descriptor(socket_type descriptor,
       // The descriptor will be automatically removed from the epoll set when
       // it is closed.
     }
-    else
+    else if (descriptor_data->registered_events_ != 0)
     {
       epoll_event ev = { 0, { 0 } };
       epoll_ctl(epoll_fd_, EPOLL_CTL_DEL, descriptor, &ev);