diff --git a/applications/utilities/mesh/manipulation/createPatch/createPatch.C b/applications/utilities/mesh/manipulation/createPatch/createPatch.C
index 9a8dcd47db..f15ad18ce1 100644
--- a/applications/utilities/mesh/manipulation/createPatch/createPatch.C
+++ b/applications/utilities/mesh/manipulation/createPatch/createPatch.C
@@ -606,7 +606,7 @@ void syncPoints
                 pointField nbrPatchInfo(procPatch.nPoints());
                 {
                     // We do not know the number of points on the other side
-                    // so cannot use Pstream::read.
+                    // so cannot use UIPstream::read
                     IPstream fromNbr
                     (
                         Pstream::commsTypes::blocking,
diff --git a/src/OpenFOAM/db/IOobjects/decomposedBlockData/decomposedBlockData.C b/src/OpenFOAM/db/IOobjects/decomposedBlockData/decomposedBlockData.C
index 31003c8293..61b8732963 100644
--- a/src/OpenFOAM/db/IOobjects/decomposedBlockData/decomposedBlockData.C
+++ b/src/OpenFOAM/db/IOobjects/decomposedBlockData/decomposedBlockData.C
@@ -789,7 +789,7 @@ bool Foam::decomposedBlockData::writeBlocks
             for (label proci = 1; proci < nProcs; ++proci)
             {
                 elems.resize(recvSizes[proci]);
-                IPstream::read
+                UIPstream::read
                 (
                     UPstream::commsTypes::scheduled,
                     proci,
diff --git a/src/OpenFOAM/fields/pointPatchFields/constraint/processorCyclic/processorCyclicPointPatchField.C b/src/OpenFOAM/fields/pointPatchFields/constraint/processorCyclic/processorCyclicPointPatchField.C
index 0e4ab1e9e5..5abd549408 100644
--- a/src/OpenFOAM/fields/pointPatchFields/constraint/processorCyclic/processorCyclicPointPatchField.C
+++ b/src/OpenFOAM/fields/pointPatchFields/constraint/processorCyclic/processorCyclicPointPatchField.C
@@ -119,7 +119,7 @@ void Foam::processorCyclicPointPatchField<Type>::initSwapAddSeparated
         if (commsType == Pstream::commsTypes::nonBlocking)
         {
             receiveBuf_.setSize(pf.size());
-            IPstream::read
+            UIPstream::read
             (
                 commsType,
                 procPatch_.neighbProcNo(),
@@ -129,7 +129,7 @@ void Foam::processorCyclicPointPatchField<Type>::initSwapAddSeparated
                 procPatch_.comm()
             );
         }
-        OPstream::write
+        UOPstream::write
         (
             commsType,
             procPatch_.neighbProcNo(),
@@ -155,7 +155,7 @@ void Foam::processorCyclicPointPatchField<Type>::swapAddSeparated
         if (commsType != Pstream::commsTypes::nonBlocking)
         {
             receiveBuf_.setSize(this->size());
-            IPstream::read
+            UIPstream::read
             (
                 commsType,
                 procPatch_.neighbProcNo(),
diff --git a/src/OpenFOAM/matrices/LUscalarMatrix/LUscalarMatrix.C b/src/OpenFOAM/matrices/LUscalarMatrix/LUscalarMatrix.C
index a8e5666060..65468a617c 100644
--- a/src/OpenFOAM/matrices/LUscalarMatrix/LUscalarMatrix.C
+++ b/src/OpenFOAM/matrices/LUscalarMatrix/LUscalarMatrix.C
@@ -86,7 +86,7 @@ Foam::LUscalarMatrix::LUscalarMatrix
 
         if (Pstream::master(comm_))
         {
-            for (const int slave : Pstream::subProcs(comm_))
+            for (const int proci : Pstream::subProcs(comm_))
             {
                 lduMatrices.set
                 (
@@ -96,7 +96,7 @@ Foam::LUscalarMatrix::LUscalarMatrix
                         IPstream
                         (
                             Pstream::commsTypes::scheduled,
-                            slave,
+                            proci,
                             0,          // bufSize
                             Pstream::msgType(),
                             comm_
diff --git a/src/OpenFOAM/matrices/LUscalarMatrix/LUscalarMatrixTemplates.C b/src/OpenFOAM/matrices/LUscalarMatrix/LUscalarMatrixTemplates.C
index 159a6af98f..568275e54c 100644
--- a/src/OpenFOAM/matrices/LUscalarMatrix/LUscalarMatrixTemplates.C
+++ b/src/OpenFOAM/matrices/LUscalarMatrix/LUscalarMatrixTemplates.C
@@ -54,17 +54,17 @@ void Foam::LUscalarMatrix::solve
 
             SubList<Type>(X, x.size()) = x;
 
-            for (const int slave : Pstream::subProcs(comm_))
+            for (const int proci : Pstream::subProcs(comm_))
             {
-                IPstream::read
+                UIPstream::read
                 (
                     Pstream::commsTypes::scheduled,
-                    slave,
+                    proci,
                     reinterpret_cast<char*>
                     (
-                        &(X[procOffsets_[slave]])
+                        &(X[procOffsets_[proci]])
                     ),
-                    (procOffsets_[slave+1]-procOffsets_[slave])*sizeof(Type),
+                    (procOffsets_[proci+1]-procOffsets_[proci])*sizeof(Type),
                     Pstream::msgType(),
                     comm_
                 );
@@ -72,7 +72,7 @@ void Foam::LUscalarMatrix::solve
         }
         else
         {
-            OPstream::write
+            UOPstream::write
             (
                 Pstream::commsTypes::scheduled,
                 Pstream::masterNo(),
@@ -89,17 +89,17 @@ void Foam::LUscalarMatrix::solve
 
             x = SubList<Type>(X, x.size());
 
-            for (const int slave : Pstream::subProcs(comm_))
+            for (const int proci : Pstream::subProcs(comm_))
             {
-                OPstream::write
+                UOPstream::write
                 (
                     Pstream::commsTypes::scheduled,
-                    slave,
+                    proci,
                     reinterpret_cast<const char*>
                     (
-                        &(X[procOffsets_[slave]])
+                        &(X[procOffsets_[proci]])
                     ),
-                    (procOffsets_[slave+1]-procOffsets_[slave])*sizeof(Type),
+                    (procOffsets_[proci+1]-procOffsets_[proci])*sizeof(Type),
                     Pstream::msgType(),
                     comm_
                 );
@@ -107,7 +107,7 @@ void Foam::LUscalarMatrix::solve
         }
         else
         {
-            IPstream::read
+            UIPstream::read
             (
                 Pstream::commsTypes::scheduled,
                 Pstream::masterNo(),
diff --git a/src/OpenFOAM/matrices/lduMatrix/lduAddressing/lduInterface/processorLduInterfaceTemplates.C b/src/OpenFOAM/matrices/lduMatrix/lduAddressing/lduInterface/processorLduInterfaceTemplates.C
index fa2292c6e5..875d202faa 100644
--- a/src/OpenFOAM/matrices/lduMatrix/lduAddressing/lduInterface/processorLduInterfaceTemplates.C
+++ b/src/OpenFOAM/matrices/lduMatrix/lduAddressing/lduInterface/processorLduInterfaceTemplates.C
@@ -47,7 +47,7 @@ void Foam::processorLduInterface::send
      || commsType == Pstream::commsTypes::scheduled
     )
     {
-        OPstream::write
+        UOPstream::write
         (
             commsType,
             neighbProcNo(),
@@ -61,7 +61,7 @@ void Foam::processorLduInterface::send
     {
         resizeBuf(receiveBuf_, nBytes);
 
-        IPstream::read
+        UIPstream::read
         (
             commsType,
             neighbProcNo(),
@@ -77,7 +77,7 @@ void Foam::processorLduInterface::send
             static_cast<void*>(sendBuf_.data()), f.cdata(), nBytes
         );
 
-        OPstream::write
+        UOPstream::write
         (
             commsType,
             neighbProcNo(),
@@ -109,7 +109,7 @@ void Foam::processorLduInterface::receive
      || commsType == Pstream::commsTypes::scheduled
     )
     {
-        IPstream::read
+        UIPstream::read
         (
             commsType,
             neighbProcNo(),
@@ -181,7 +181,7 @@ void Foam::processorLduInterface::compressedSend
          || commsType == Pstream::commsTypes::scheduled
         )
         {
-            OPstream::write
+            UOPstream::write
             (
                 commsType,
                 neighbProcNo(),
@@ -195,7 +195,7 @@ void Foam::processorLduInterface::compressedSend
         {
             resizeBuf(receiveBuf_, nBytes);
 
-            IPstream::read
+            UIPstream::read
             (
                 commsType,
                 neighbProcNo(),
@@ -205,7 +205,7 @@ void Foam::processorLduInterface::compressedSend
                 comm()
             );
 
-            OPstream::write
+            UOPstream::write
             (
                 commsType,
                 neighbProcNo(),
@@ -252,7 +252,7 @@ void Foam::processorLduInterface::compressedReceive
         {
             resizeBuf(receiveBuf_, nBytes);
 
-            IPstream::read
+            UIPstream::read
             (
                 commsType,
                 neighbProcNo(),
diff --git a/src/OpenFOAM/matrices/lduMatrix/solvers/GAMG/GAMGSolverAgglomerateMatrix.C b/src/OpenFOAM/matrices/lduMatrix/solvers/GAMG/GAMGSolverAgglomerateMatrix.C
index 6e0a01f9cd..a6dc781272 100644
--- a/src/OpenFOAM/matrices/lduMatrix/solvers/GAMG/GAMGSolverAgglomerateMatrix.C
+++ b/src/OpenFOAM/matrices/lduMatrix/solvers/GAMG/GAMGSolverAgglomerateMatrix.C
@@ -318,7 +318,7 @@ void Foam::GAMGSolver::gatherMatrices
         {
             label otherI = proci-1;
 
-            IPstream fromSlave
+            IPstream fromProc
             (
                 Pstream::commsTypes::scheduled,
                 procIDs[proci],
@@ -327,14 +327,14 @@ void Foam::GAMGSolver::gatherMatrices
                 meshComm
             );
 
-            otherMats.set(otherI, new lduMatrix(dummyMesh, fromSlave));
+            otherMats.set(otherI, new lduMatrix(dummyMesh, fromProc));
 
             // Receive number of/valid interfaces
             boolList& procTransforms = otherTransforms[otherI];
             List<label>& procRanks = otherRanks[otherI];
 
-            fromSlave >> procTransforms;
-            fromSlave >> procRanks;
+            fromProc >> procTransforms;
+            fromProc >> procRanks;
 
             // Size coefficients
             otherBouCoeffs.set
@@ -354,12 +354,12 @@ void Foam::GAMGSolver::gatherMatrices
                     otherBouCoeffs[otherI].set
                     (
                         intI,
-                        new scalarField(fromSlave)
+                        new scalarField(fromProc)
                     );
                     otherIntCoeffs[otherI].set
                     (
                         intI,
-                        new scalarField(fromSlave)
+                        new scalarField(fromProc)
                     );
                 }
             }
diff --git a/src/OpenFOAM/matrices/lduMatrix/solvers/GAMG/interfaceFields/processorGAMGInterfaceField/processorGAMGInterfaceField.C b/src/OpenFOAM/matrices/lduMatrix/solvers/GAMG/interfaceFields/processorGAMGInterfaceField/processorGAMGInterfaceField.C
index 13ff33c5d5..0cf63ba1f3 100644
--- a/src/OpenFOAM/matrices/lduMatrix/solvers/GAMG/interfaceFields/processorGAMGInterfaceField/processorGAMGInterfaceField.C
+++ b/src/OpenFOAM/matrices/lduMatrix/solvers/GAMG/interfaceFields/processorGAMGInterfaceField/processorGAMGInterfaceField.C
@@ -110,7 +110,7 @@ void Foam::processorGAMGInterfaceField::initInterfaceMatrixUpdate
         // Fast path.
         scalarReceiveBuf_.setSize(scalarSendBuf_.size());
         outstandingRecvRequest_ = UPstream::nRequests();
-        IPstream::read
+        UIPstream::read
         (
             Pstream::commsTypes::nonBlocking,
             procInterface_.neighbProcNo(),
@@ -121,7 +121,7 @@ void Foam::processorGAMGInterfaceField::initInterfaceMatrixUpdate
         );
 
         outstandingSendRequest_ = UPstream::nRequests();
-        OPstream::write
+        UOPstream::write
         (
             Pstream::commsTypes::nonBlocking,
             procInterface_.neighbProcNo(),
diff --git a/src/OpenFOAM/meshes/lduMesh/lduPrimitiveMesh.C b/src/OpenFOAM/meshes/lduMesh/lduPrimitiveMesh.C
index 45177b822b..0c2e4c087b 100644
--- a/src/OpenFOAM/meshes/lduMesh/lduPrimitiveMesh.C
+++ b/src/OpenFOAM/meshes/lduMesh/lduPrimitiveMesh.C
@@ -1092,15 +1092,15 @@ void Foam::lduPrimitiveMesh::gather
 
     if (Pstream::myProcNo(comm) == procIDs[0])
     {
+        // Master.
         otherMeshes.setSize(procIDs.size()-1);
 
-        // Slave meshes
         for (label i = 1; i < procIDs.size(); ++i)
         {
             //Pout<< "on master :"
-            //    << " receiving from slave " << procIDs[i] << endl;
+            //    << " receiving from proc " << procIDs[i] << endl;
 
-            IPstream fromSlave
+            IPstream fromProc
             (
                 Pstream::commsTypes::scheduled,
                 procIDs[i],
@@ -1109,10 +1109,10 @@ void Foam::lduPrimitiveMesh::gather
                 comm
             );
 
-            label nCells = readLabel(fromSlave);
-            labelList lowerAddr(fromSlave);
-            labelList upperAddr(fromSlave);
-            boolList validInterface(fromSlave);
+            label nCells = readLabel(fromProc);
+            labelList lowerAddr(fromProc);
+            labelList upperAddr(fromProc);
+            boolList validInterface(fromProc);
 
 
             // Construct mesh without interfaces
@@ -1135,7 +1135,7 @@ void Foam::lduPrimitiveMesh::gather
             {
                 if (validInterface[intI])
                 {
-                    word coupleType(fromSlave);
+                    word coupleType(fromProc);
 
                     newInterfaces.set
                     (
@@ -1145,7 +1145,7 @@ void Foam::lduPrimitiveMesh::gather
                             coupleType,
                             intI,
                             otherMeshes[i-1].rawInterfaces(),
-                            fromSlave
+                            fromProc
                         ).ptr()
                     );
                 }
diff --git a/src/OpenFOAM/meshes/polyMesh/mapPolyMesh/mapDistribute/mapDistributeBaseSubset.C b/src/OpenFOAM/meshes/polyMesh/mapPolyMesh/mapDistribute/mapDistributeBaseSubset.C
index 9eedb3ee3d..e45a2ed0d8 100644
--- a/src/OpenFOAM/meshes/polyMesh/mapPolyMesh/mapDistribute/mapDistributeBaseSubset.C
+++ b/src/OpenFOAM/meshes/polyMesh/mapPolyMesh/mapDistribute/mapDistributeBaseSubset.C
@@ -158,7 +158,7 @@ void Foam::mapDistributeBase::exchangeMasks
         {
             if (proci != myRank && recvMasks[proci].size())
             {
-                IPstream::read
+                UIPstream::read
                 (
                     UPstream::commsTypes::nonBlocking,
                     proci,
@@ -174,7 +174,7 @@ void Foam::mapDistributeBase::exchangeMasks
         {
             if (proci != myRank && sendMasks[proci].size())
             {
-                OPstream::write
+                UOPstream::write
                 (
                     UPstream::commsTypes::nonBlocking,
                     proci,
diff --git a/src/OpenFOAM/meshes/polyMesh/mapPolyMesh/mapDistribute/mapDistributeBaseTemplates.C b/src/OpenFOAM/meshes/polyMesh/mapPolyMesh/mapDistribute/mapDistributeBaseTemplates.C
index ca80a622c6..6580cd3052 100644
--- a/src/OpenFOAM/meshes/polyMesh/mapPolyMesh/mapDistribute/mapDistributeBaseTemplates.C
+++ b/src/OpenFOAM/meshes/polyMesh/mapPolyMesh/mapDistribute/mapDistributeBaseTemplates.C
@@ -520,7 +520,7 @@ void Foam::mapDistributeBase::distribute
                     sendFields[domain] =
                         accessAndFlip(field, map, subHasFlip, negOp);
 
-                    OPstream::write
+                    UOPstream::write
                     (
                         Pstream::commsTypes::nonBlocking,
                         domain,
@@ -543,8 +543,7 @@ void Foam::mapDistributeBase::distribute
                 if (domain != myRank && map.size())
                 {
                     recvFields[domain].resize(map.size());
-
-                    IPstream::read
+                    UIPstream::read
                     (
                         Pstream::commsTypes::nonBlocking,
                         domain,
@@ -556,7 +555,6 @@ void Foam::mapDistributeBase::distribute
                 }
             }
 
-
             // Set up 'send' to myself
             {
                 sendFields[myRank] =
@@ -982,7 +980,7 @@ void Foam::mapDistributeBase::distribute
                     sendFields[domain] =
                         accessAndFlip(field, map, subHasFlip, negOp);
 
-                    OPstream::write
+                    UOPstream::write
                     (
                         Pstream::commsTypes::nonBlocking,
                         domain,
@@ -1004,7 +1002,7 @@ void Foam::mapDistributeBase::distribute
 
                 if (domain != myRank && map.size())
                 {
-                    recvFields[domain].setSize(map.size());
+                    recvFields[domain].resize(map.size());
                     UIPstream::read
                     (
                         Pstream::commsTypes::nonBlocking,
@@ -1018,7 +1016,6 @@ void Foam::mapDistributeBase::distribute
             }
 
             // Set up 'send' to myself
-
             {
                 sendFields[myRank] =
                     accessAndFlip(field, subMap[myRank], subHasFlip, negOp);
diff --git a/src/OpenFOAM/meshes/polyMesh/syncTools/syncToolsTemplates.C b/src/OpenFOAM/meshes/polyMesh/syncTools/syncToolsTemplates.C
index 9f16a7c17b..b2d3e03e95 100644
--- a/src/OpenFOAM/meshes/polyMesh/syncTools/syncToolsTemplates.C
+++ b/src/OpenFOAM/meshes/polyMesh/syncTools/syncToolsTemplates.C
@@ -1029,7 +1029,7 @@ void Foam::syncTools::syncBoundaryFaceList
                         pp.start()-boundaryOffset
                     );
 
-                    IPstream::read
+                    UIPstream::read
                     (
                         Pstream::commsTypes::nonBlocking,
                         procPatch.neighbProcNo(),
@@ -1055,7 +1055,7 @@ void Foam::syncTools::syncBoundaryFaceList
                         pp.start()-boundaryOffset
                     );
 
-                    OPstream::write
+                    UOPstream::write
                     (
                         Pstream::commsTypes::nonBlocking,
                         procPatch.neighbProcNo(),
@@ -1261,7 +1261,7 @@ void Foam::syncTools::syncFaceList
                 recvInfos.set(patchi, new PackedList<Width>(patchSize));
                 PackedList<Width>& recvInfo = recvInfos[patchi];
 
-                IPstream::read
+                UIPstream::read
                 (
                     Pstream::commsTypes::nonBlocking,
                     procPatch.neighbProcNo(),
@@ -1296,7 +1296,7 @@ void Foam::syncTools::syncFaceList
                 );
                 PackedList<Width>& sendInfo = sendInfos[patchi];
 
-                OPstream::write
+                UOPstream::write
                 (
                     Pstream::commsTypes::nonBlocking,
                     procPatch.neighbProcNo(),
diff --git a/src/OpenFOAM/parallel/globalIndex/globalIndexTemplates.C b/src/OpenFOAM/parallel/globalIndex/globalIndexTemplates.C
index 2029ea4f07..33d0a71397 100644
--- a/src/OpenFOAM/parallel/globalIndex/globalIndexTemplates.C
+++ b/src/OpenFOAM/parallel/globalIndex/globalIndexTemplates.C
@@ -100,7 +100,7 @@ void Foam::globalIndex::gatherValues
         {
             if (is_contiguous<Type>::value)
             {
-                IPstream::read
+                UIPstream::read
                 (
                     commsType,
                     procIDs[i],
@@ -123,7 +123,7 @@ void Foam::globalIndex::gatherValues
 
         if (is_contiguous<Type>::value)
         {
-            OPstream::write
+            UOPstream::write
             (
                 commsType,
                 procIDs[0],
@@ -198,7 +198,7 @@ void Foam::globalIndex::gather
             }
             else if (is_contiguous<Type>::value)
             {
-                IPstream::read
+                UIPstream::read
                 (
                     commsType,
                     procIDs[i],
@@ -223,7 +223,7 @@ void Foam::globalIndex::gather
         }
         else if (is_contiguous<Type>::value)
         {
-            OPstream::write
+            UOPstream::write
             (
                 commsType,
                 procIDs[0],
@@ -889,7 +889,7 @@ void Foam::globalIndex::scatter
             }
             else if (is_contiguous<Type>::value)
             {
-                OPstream::write
+                UOPstream::write
                 (
                     commsType,
                     procIDs[i],
@@ -926,7 +926,7 @@ void Foam::globalIndex::scatter
         }
         else if (is_contiguous<Type>::value)
         {
-            IPstream::read
+            UIPstream::read
             (
                 commsType,
                 procIDs[0],
diff --git a/src/finiteArea/faMesh/faMeshDemandDrivenData.C b/src/finiteArea/faMesh/faMeshDemandDrivenData.C
index e23ed0d592..397732b70e 100644
--- a/src/finiteArea/faMesh/faMeshDemandDrivenData.C
+++ b/src/finiteArea/faMesh/faMeshDemandDrivenData.C
@@ -1177,7 +1177,7 @@ void Foam::faMesh::calcPointAreaNormals(vectorField& result) const
             );
 
             {
-                OPstream::write
+                UOPstream::write
                 (
                     Pstream::commsTypes::blocking,
                     procPatch.neighbProcNo(),
@@ -1190,7 +1190,7 @@ void Foam::faMesh::calcPointAreaNormals(vectorField& result) const
             patchPointNormals.resize(nbrPatchPoints.size());
 
             {
-                IPstream::read
+                UIPstream::read
                 (
                     Pstream::commsTypes::blocking,
                     procPatch.neighbProcNo(),
diff --git a/src/finiteVolume/fields/fvPatchFields/constraint/processor/processorFvPatchField.C b/src/finiteVolume/fields/fvPatchFields/constraint/processor/processorFvPatchField.C
index c20c39879e..19a38e1804 100644
--- a/src/finiteVolume/fields/fvPatchFields/constraint/processor/processorFvPatchField.C
+++ b/src/finiteVolume/fields/fvPatchFields/constraint/processor/processorFvPatchField.C
@@ -506,7 +506,7 @@ void Foam::processorFvPatchField<Type>::initInterfaceMatrixUpdate
 
         receiveBuf_.setSize(sendBuf_.size());
         outstandingRecvRequest_ = UPstream::nRequests();
-        IPstream::read
+        UIPstream::read
         (
             Pstream::commsTypes::nonBlocking,
             procPatch_.neighbProcNo(),
@@ -517,7 +517,7 @@ void Foam::processorFvPatchField<Type>::initInterfaceMatrixUpdate
         );
 
         outstandingSendRequest_ = UPstream::nRequests();
-        OPstream::write
+        UOPstream::write
         (
             Pstream::commsTypes::nonBlocking,
             procPatch_.neighbProcNo(),
diff --git a/src/functionObjects/lagrangian/dataCloud/dataCloudTemplates.C b/src/functionObjects/lagrangian/dataCloud/dataCloudTemplates.C
index c90205543d..b1ef6f3093 100644
--- a/src/functionObjects/lagrangian/dataCloud/dataCloudTemplates.C
+++ b/src/functionObjects/lagrangian/dataCloud/dataCloudTemplates.C
@@ -85,11 +85,11 @@ void Foam::functionObjects::dataCloud::writeListParallel
         Field<Type> recvField;
 
         // Receive and write
-        for (const int slave : Pstream::subProcs())
+        for (const int proci : Pstream::subProcs())
         {
-            IPstream fromSlave(Pstream::commsTypes::blocking, slave);
+            IPstream fromProc(Pstream::commsTypes::blocking, proci);
 
-            fromSlave >> recvPoints >> recvField;
+            fromProc >> recvPoints >> recvField;
 
             writeList(os, recvPoints, recvField);
         }
@@ -142,11 +142,11 @@ void Foam::functionObjects::dataCloud::writeListParallel
         Field<Type> recvField;
 
         // Receive and write
-        for (const int slave : Pstream::subProcs())
+        for (const int proci : Pstream::subProcs())
         {
-            IPstream fromSlave(Pstream::commsTypes::blocking, slave);
+            IPstream fromProc(Pstream::commsTypes::blocking, proci);
 
-            fromSlave >> recvPoints >> recvField;
+            fromProc >> recvPoints >> recvField;
 
             writeList(os, recvPoints, recvField);
         }
diff --git a/src/overset/lduPrimitiveProcessorInterface/GAMG/calculatedProcessorGAMGInterfaceField.C b/src/overset/lduPrimitiveProcessorInterface/GAMG/calculatedProcessorGAMGInterfaceField.C
index c67e0922c8..881cd30fdc 100644
--- a/src/overset/lduPrimitiveProcessorInterface/GAMG/calculatedProcessorGAMGInterfaceField.C
+++ b/src/overset/lduPrimitiveProcessorInterface/GAMG/calculatedProcessorGAMGInterfaceField.C
@@ -111,7 +111,7 @@ void Foam::calculatedProcessorGAMGInterfaceField::initInterfaceMatrixUpdate
         // Fast path.
         scalarReceiveBuf_.setSize(scalarSendBuf_.size());
         outstandingRecvRequest_ = UPstream::nRequests();
-        IPstream::read
+        UIPstream::read
         (
             Pstream::commsTypes::nonBlocking,
             procInterface_.neighbProcNo(),
@@ -122,7 +122,7 @@ void Foam::calculatedProcessorGAMGInterfaceField::initInterfaceMatrixUpdate
         );
 
         outstandingSendRequest_ = UPstream::nRequests();
-        OPstream::write
+        UOPstream::write
         (
             Pstream::commsTypes::nonBlocking,
             procInterface_.neighbProcNo(),
diff --git a/src/parallel/decompose/decompositionMethods/metisLikeDecomp/metisLikeDecomp.C b/src/parallel/decompose/decompositionMethods/metisLikeDecomp/metisLikeDecomp.C
index 48636a9a0c..2dfa932c4b 100644
--- a/src/parallel/decompose/decompositionMethods/metisLikeDecomp/metisLikeDecomp.C
+++ b/src/parallel/decompose/decompositionMethods/metisLikeDecomp/metisLikeDecomp.C
@@ -94,7 +94,7 @@ Foam::label Foam::metisLikeDecomp::decomposeGeneral
             }
             else
             {
-                IPstream::read
+                UIPstream::read
                 (
                     commsType,
                     proci,
@@ -118,7 +118,7 @@ Foam::label Foam::metisLikeDecomp::decomposeGeneral
         {
             SubList<label> procSlot(xadj, numCells);
 
-            OPstream::write
+            UOPstream::write
             (
                 commsType,
                 UPstream::masterNo(),
diff --git a/src/sampling/surface/isoSurface/isoSurfacePoint.C b/src/sampling/surface/isoSurface/isoSurfacePoint.C
index caae144e79..21b34190b9 100644
--- a/src/sampling/surface/isoSurface/isoSurfacePoint.C
+++ b/src/sampling/surface/isoSurface/isoSurfacePoint.C
@@ -184,7 +184,7 @@ void Foam::isoSurfacePoint::syncUnseparatedPoints
                 pointField nbrPatchInfo(procPatch.nPoints());
                 {
                     // We do not know the number of points on the other side
-                    // so cannot use Pstream::read.
+                    // so cannot use UIPstream::read
                     IPstream fromNbr
                     (
                         Pstream::commsTypes::blocking,