ENH: adding hook adjustTimeStep to function objects. The hook is called in

Time::adjustDeltaT(). It allows function objects to manipulate the time step to
    dump at adjustable times. The following options are available for output in
    function objects: timeStep, outputTime, adjustableTime, runTime, clockTime
    and cpuTime.

src/postProcessing/functionObjects/IO/controlDict

@@ -64,14 +64,24 @@ functions
         // region allowed.
         region wallFilmRegion;
 
-        // Execute upon outputTime
+        // Execute upon options:
+        //  timeStep
+        //  outputTime
+        //  adjustableTime
+        //  runTime
+        //  clockTime
+        //  cpuTime
         outputControl   outputTime;
 
         // Objects (fields or lagrangian fields in any of the clouds)
         // to write every outputTime
         objectNames    (p positions nParticle);
+
         // Write as normal every writeInterval'th outputTime.
-        writeInterval   3;
+        outputInterval  1; // (timeStep, outputTime)
+
+        // Interval of time (sec) to write down(
+        writeInterval   10.5 //(adjustableTime, runTime, clockTime, cpuTime)
     }
 
     dumpObjects
@@ -84,9 +94,24 @@ functions
         // Where to load it from
         functionObjectLibs ("libIOFunctionObjects.so");
 
-        // Execute upon outputTime
+        // Execute upon outputTime:
+        //  timeStep
+        //  outputTime
+        //  adjustableTime
+        //  runTime
+        //  clockTime
+        //  cpuTime
         outputControl   outputTime;
 
+        // Is the object written by this function Object alone
+        exclusiveWriting       true;
+
+         // Interval of time (sec) to write down(
+        writeInterval   10.5 //(adjustableTime, runTime, clockTime, cpuTime)
+
+         // Write as normal every writeInterval'th outputTime.
+        outputInterval  1; // (timeStep, outputTime)
+
         // Objects to write
         objectNames    ();
     }

src/postProcessing/functionObjects/IO/writeRegisteredObject/writeRegisteredObject.C

@@ -46,6 +46,7 @@ Foam::writeRegisteredObject::writeRegisteredObject
 )
 :
     name_(name),
+    exclusiveWriting_(true),
     obr_(obr),
     objectNames_()
 {
@@ -64,6 +65,7 @@ Foam::writeRegisteredObject::~writeRegisteredObject()
 void Foam::writeRegisteredObject::read(const dictionary& dict)
 {
     dict.lookup("objectNames") >> objectNames_;
+    dict.readIfPresent("exclusiveWriting", exclusiveWriting_);
 }
 
 
@@ -96,12 +98,12 @@ void Foam::writeRegisteredObject::write()
                 (
                     obr_.lookupObject<regIOobject>(objectNames_[i])
                 );
-            // Switch off automatic writing to prevent double write
-            obj.writeOpt() = IOobject::NO_WRITE;
 
-            Info<< type() << " " << name_ << " output:" << nl
-                << "    writing object " << obj.name() << nl
-                << endl;
+            if (exclusiveWriting_)
+            {
+                // Switch off automatic writing to prevent double write
+                obj.writeOpt() = IOobject::NO_WRITE;
+            }
 
             obj.write();
         }

src/postProcessing/functionObjects/IO/writeRegisteredObject/writeRegisteredObject.H

@@ -28,8 +28,15 @@ Group
     grpIOFunctionObjects
 
 Description
-    This function object takes-over the writing of objects registered to the
-    database.
+    This function object allows specification of different writing frequency
+    of objects registered to the database. It has similar functionality
+    as the main time database through the outputControl setting:
+        timeStep
+        outputTime
+        adjustableTime
+        runTime
+        clockTime
+        cpuTime
 
     Example of function object specification:
     \verbatim
@@ -37,6 +44,7 @@ Description
     {
         type        writeRegisteredObject;
         functionObjectLibs ("libIOFunctionObjects.so");
+        exclusiveWriting     true;
         ...
         objectNames (obj1 obj2);
     }
@@ -47,8 +55,12 @@ Description
         Property     | Description             | Required    | Default value
         type         | type name: writeRegisteredObject | yes |
         objectNames  | objects to write        | yes         |
+        exclusiveWriting    | Takes over object writing | no | yes
     \endtable
 
+    exclusiveWriting disables automatic writing (i.e through database) of the
+    objects to avoid duplicate writing.
+
 SeeAlso
     Foam::functionObject
     Foam::OutputFilterFunctionObject
@@ -89,6 +101,9 @@ protected:
         //- Name of this set of writeRegisteredObject
         word name_;
 
+        //- Takes over the writing from Db
+        bool exclusiveWriting_;
+
         const objectRegistry& obr_;
 
         // Read from dictionary