use os.put() for single chars

Log.cpp

@@ -32,7 +32,8 @@ public:
 
 		std::ostream* os = getOs(lvl);
 		if (os) {
-			*os << sbuf << '\n';
+			*os << sbuf;
+			os->put('\n');
 		}
 	};
 
@@ -83,7 +84,7 @@ private:
 			else
 				*os << sbuf;
 
-			*os << '\n';
+			os->put('\n');
 		}
 	}
 
@@ -191,7 +192,7 @@ void init() {
 	// set default entry metadata printing functions
 	auto space = [](std::ostream& os, const Entry& e) -> std::ostream& {
 		(void) e;
-		return os << ' ';
+		return os.put(' ');
 	};
 	entryMetaFunctions = {
 		defaultEntryMetaTime,