Small improvements for code clarity

Do not use the "file2" ofstream variable name, but pick something
more descriptive and initialised closer to its point of use.

Remove the JSON dictrionary references and use the "Max" and
"Avg" keys directly.

package/src/prmon.cpp

@@ -168,7 +168,6 @@ int MemoryMonitor(const pid_t mpid, const std::string filename,
 
   Document d;
   d.Parse(json.str().c_str());
-  std::ofstream file2;  // for realtime json dict
   StringBuffer buffer;
   Writer<StringBuffer> writer(buffer);
 
@@ -177,9 +176,6 @@ int MemoryMonitor(const pid_t mpid, const std::string filename,
   std::stringstream newFile;
   newFile << jsonSummary << "_snapshot";
 
-  Value& v1 = d["Max"];
-  Value& v2 = d["Avg"];
-
   // Monitoring loop until process exits
   while (kill(mpid, 0) == 0 && sigusr1 == false) {
     bool wroteFile = false;
@@ -206,18 +202,18 @@ int MemoryMonitor(const pid_t mpid, const std::string filename,
       // Create JSON realtime summary
       for (const auto monitor : monitors)
         for (const auto& stat : monitor->get_json_total_stats())
-          v1[(stat.first).c_str()].SetUint64(stat.second);
+          d["Max"][(stat.first).c_str()].SetUint64(stat.second);
       for (const auto monitor : monitors)
         for (const auto& stat : monitor->get_json_average_stats(
-            wall_monitor.get_wallclock_clock_t()))
-        v2[(stat.first).c_str()].SetUint64(stat.second);
+                 wall_monitor.get_wallclock_clock_t()))
+          d["Avg"][(stat.first).c_str()].SetUint64(stat.second);
 
       // Write JSON realtime summary to a temporary file (to avoid race
       // conditions with pilot trying to read from file at the same time)
       d.Accept(writer);
-      file2.open(tmpFile.str());
-      file2 << buffer.GetString() << std::endl;
-      file2.close();
+      std::ofstream json_out(tmpFile.str());
+      json_out << buffer.GetString() << std::endl;
+      json_out.close();
       wroteFile = true;
     }