Further fixes for OptionProxy. Some cosmetics in the docs

apps/apputil.hpp

@@ -350,22 +350,41 @@ struct OptionSetterProxy
 
     struct OptionProxy
     {
-        const OptionSetterProxy& parent;
+        OptionSetterProxy& parent;
         SRT_SOCKOPT opt;
 
-        template<class Type>
-        OptionProxy& operator=(Type&& val)
+#define SPEC(type) \
+        OptionProxy& operator=(const type& val)\
+        {\
+            parent.result = srt_setsockflag(parent.s, opt, &val, sizeof val);\
+            return *this;\
+        }
+
+        SPEC(int32_t);
+        SPEC(int64_t);
+        SPEC(bool);
+#undef SPEC
+
+        template<size_t N>
+        OptionProxy& operator=(const char (&val)[N])
+        {
+            parent.result = srt_setsockflag(parent.s, opt, val, N-1);
+            return *this;
+        }
+
+        OptionProxy& operator=(const std::string& val)
         {
-            Type vc(val);
-            srt_setsockflag(parent.s, opt, &vc, sizeof vc);
+            parent.result = srt_setsockflag(parent.s, opt, val.c_str(), val.size());
             return *this;
         }
     };
 
-    OptionProxy operator[](SRT_SOCKOPT opt) const
+    OptionProxy operator[](SRT_SOCKOPT opt)
     {
         return OptionProxy {*this, opt};
     }
+
+    operator int() { return result; }
 };
 
 inline OptionSetterProxy setopt(SRTSOCKET socket)

docs/API/API-functions.md

@@ -639,7 +639,7 @@ below).
 * `addrlen`: INPUT: size of `addr` pointed object. OUTPUT: real size of the
 returned object
 
-General requirements for parameter correctness:
+General requirements for a parameter correctness:
 
 * `lsn` must be first [bound](#srt_bind) and [listening](#srt_listen)
 
@@ -656,7 +656,7 @@ depends on the address type used in the `srt_bind` call for `lsn`.
 If unsure in a particular situation, it is recommended that you use
 `sockaddr_storage` or `srt::sockaddr_any`.
 
-If the `lsn` listener socket is blocking mode (if
+If the `lsn` listener socket is in the blocking mode (if
 [`SRTO_RCVSYN`](API-socket-options.md#SRTO_RCVSYN) is set to true,
 which is default), the call will block until the incoming connection is ready
 for extraction. Otherwise, the call always returns immediately, possibly with
@@ -707,6 +707,8 @@ request. This feature is prone to more tricky rules, however:
       continue blocking. If you want to use only one thread for accepting
       connections from potentially multiple listening sockets in the blocking
       mode, you should use [`srt_accept_bond`](#srt_accept_bond) instead.
+      Note though that this function is actually a wrapper that changes locally 
+      to the nonblocking mode on all these listeners and uses epoll internally.
 
     * If at the moment multiple listener sockets have received connection
       request and you query them all for readiness epoll flags (by calling