diff --git a/src/OpenFOAM/db/IOstreams/Pstreams/OPstream.C b/src/OpenFOAM/db/IOstreams/Pstreams/OPstream.C
new file mode 100644
index 000000000..7e1c17b02
--- /dev/null
+++ b/src/OpenFOAM/db/IOstreams/Pstreams/OPstream.C
@@ -0,0 +1,229 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright held by original author
+     \\/     M anipulation  |
+-------------------------------------------------------------------------------
+License
+    This file is part of OpenFOAM.
+
+    OpenFOAM is free software; you can redistribute it and/or modify it
+    under the terms of the GNU General Public License as published by the
+    Free Software Foundation; either version 2 of the License, or (at your
+    option) any later version.
+
+    OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
+    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+    for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with OpenFOAM; if not, write to the Free Software Foundation,
+    Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+
+Description
+    Write primitive and binary block from OPstream
+
+\*---------------------------------------------------------------------------*/
+
+#include "error.H"
+
+#include "OPstream.H"
+#include "int.H"
+#include "token.H"
+
+#include <cctype>
+
+// * * * * * * * * * * * * * Private member functions  * * * * * * * * * * * //
+
+template<class T>
+inline void Foam::OPstream::writeToBuffer(const T& t)
+{
+    writeToBuffer(&t, sizeof(T), sizeof(T));
+}
+
+
+inline void Foam::OPstream::writeToBuffer(const char& c)
+{
+    if (size_t(buf_.size()) < bufPosition_ + 1U)
+    {
+        enlargeBuffer(1);
+    }
+
+    buf_[bufPosition_] = c;
+    bufPosition_ ++;
+}
+
+
+inline void Foam::OPstream::writeToBuffer
+(
+    const void* data,
+    size_t count,
+    size_t align
+)
+{
+    label oldPos = bufPosition_;
+
+    if (align > 1)
+    {
+        // Align bufPosition. Pads bufPosition_ - oldPos characters.
+        bufPosition_ = align + ((bufPosition_ - 1) & ~(align - 1));
+    }
+
+    if (size_t(buf_.size()) < bufPosition_ + count)
+    {
+        enlargeBuffer(bufPosition_ - oldPos + count);
+    }
+
+    register char* bufPtr = &buf_[bufPosition_];
+    register const char* dataPtr = reinterpret_cast<const char*>(data);
+    register size_t i = count;
+    while (i--) *bufPtr++ = *dataPtr++;
+
+    bufPosition_ += count;
+}
+
+
+
+// * * * * * * * * * * * * * * * * Constructor * * * * * * * * * * * * * * * //
+
+Foam::OPstream::OPstream
+(
+    const commsTypes commsType,
+    const int toProcNo,
+    const label bufSize,
+    streamFormat format,
+    versionNumber version
+)
+:
+    Pstream(commsType, bufSize),
+    Ostream(format, version),
+    toProcNo_(toProcNo)
+{
+    setOpened();
+    setGood();
+
+    if (!bufSize)
+    {
+        buf_.setSize(1000);
+    }
+}
+
+
+// * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * * //
+
+Foam::Ostream& Foam::OPstream::write(const token&)
+{
+    notImplemented("Ostream& OPstream::write(const token&)");
+    setBad();
+    return *this;
+}
+
+
+Foam::Ostream& Foam::OPstream::write(const char c)
+{
+    if (!isspace(c))
+    {
+        writeToBuffer(c);
+    }
+
+    return *this;
+}
+
+
+Foam::Ostream& Foam::OPstream::write(const char* str)
+{
+    word nonWhiteChars(string::validate<word>(str));
+
+    if (nonWhiteChars.size() == 1)
+    {
+        return write(nonWhiteChars.c_str()[1]);
+    }
+    else if (nonWhiteChars.size())
+    {
+        return write(nonWhiteChars);
+    }
+    else
+    {
+        return *this;
+    }
+}
+
+
+Foam::Ostream& Foam::OPstream::write(const word& str)
+{
+    write(char(token::WORD));
+
+    size_t len = str.size();
+    writeToBuffer(len);
+    writeToBuffer(str.c_str(), len + 1, 1);
+
+    return *this;
+}
+
+
+Foam::Ostream& Foam::OPstream::write(const string& str)
+{
+    write(char(token::STRING));
+
+    size_t len = str.size();
+    writeToBuffer(len);
+    writeToBuffer(str.c_str(), len + 1, 1);
+
+    return *this;
+}
+
+
+Foam::Ostream& Foam::OPstream::writeQuoted(const std::string& str, const bool)
+{
+    write(char(token::STRING));
+
+    size_t len = str.size();
+    writeToBuffer(len);
+    writeToBuffer(str.c_str(), len + 1, 1);
+
+    return *this;
+}
+
+
+Foam::Ostream& Foam::OPstream::write(const label val)
+{
+    write(char(token::LABEL));
+    writeToBuffer(val);
+    return *this;
+}
+
+
+Foam::Ostream& Foam::OPstream::write(const floatScalar val)
+{
+    write(char(token::FLOAT_SCALAR));
+    writeToBuffer(val);
+    return *this;
+}
+
+
+Foam::Ostream& Foam::OPstream::write(const doubleScalar val)
+{
+    write(char(token::DOUBLE_SCALAR));
+    writeToBuffer(val);
+    return *this;
+}
+
+
+Foam::Ostream& Foam::OPstream::write(const char* data, std::streamsize count)
+{
+    if (format() != BINARY)
+    {
+        FatalErrorIn("Ostream::write(const char*, std::streamsize)")
+            << "stream format not binary"
+            << Foam::abort(FatalError);
+    }
+
+    writeToBuffer(data, count, 8);
+
+    return *this;
+}
+
+
+// ************************************************************************* //