diff --git a/applications/test/fileNameClean/fileNameCleanTest.C b/applications/test/fileNameClean/fileNameCleanTest.C
index 4a6824d5a4..b41cc434ca 100644
--- a/applications/test/fileNameClean/fileNameCleanTest.C
+++ b/applications/test/fileNameClean/fileNameCleanTest.C
@@ -40,137 +40,19 @@ Description
 
 using namespace Foam;
 
-//
-// * remove repeated slashes
-//       /abc////def        -->   /abc/def
-//
-// * remove '/./'
-//       /abc/def/./ghi/.   -->   /abc/def/./ghi
-//       abc/def/./         -->   abc/def
-//
-// * remove '/../'
-//       /abc/def/../ghi/jkl/nmo/..   -->   /abc/ghi/jkl
-//       abc/../def/ghi/../jkl        -->   abc/../def/jkl
-//
-// * remove trailing '/'
-//
-bool fileNameCleanThis(fileName& This)
-{
-    // the top slash - we are never allowed to descend below this one
-    register string::size_type top = This.find('/');
-
-    // no slashes - nothing to do
-    if (top == string::npos)
-    {
-        return false;
-    }
-
-    // start with the '/' found:
-    register char prev = '/';
-    register string::size_type nChar = top+1;
-    register string::size_type maxLen = This.size();
-
-    for
-    (
-        register string::size_type src = nChar;
-        src < maxLen;
-        /*nil*/
-    )
-    {
-        register char c = This[src++];
-
-        if (prev == '/')
-        {
-            // repeated '/' - skip it
-            if (c == '/')
-            {
-                continue;
-            }
-
-            // could be '/./' or '/../'
-            if (c == '.')
-            {
-                // found trailing '/.' - skip it
-                if (src >= maxLen)
-                {
-                    continue;
-                }
-
-
-                // peek at the next character
-                register char c1 = This[src];
-
-                // found '/./' - skip it
-                if (c1 == '/')
-                {
-                    src++;
-                    continue;
-                }
-
-                // it is '/..' or '/../'
-                if (c1 == '.' && (src+1 >= maxLen || This[src+1] == '/'))
-                {
-                    // find a candidate for the parent directory
-                    // minimum of 3 characters:  '/x/../'
-                    string::size_type parent =
-                    (
-                        nChar > 2
-                      ? This.rfind('/', nChar-2)
-                      : string::npos
-                    );
-
-
-                    // strip parent directory, provided that it isn't below
-                    // the current top edit point
-                    if (parent != string::npos && parent >= top)
-                    {
-                        nChar = parent + 1;
-                        src += 2;
-                        continue;
-                    }
-
-                    // bad resolution, eg 'abc/../../'
-                    // retain it, but move the top to avoid it being
-                    // considered a valid parent later
-                    top += 3;
-                }
-            }
-        }
-        This[nChar++] = prev = c;
-    }
-
-    // remove trailing slash
-    if (nChar > 1 && This[nChar-1] == '/')
-    {
-        nChar--;
-    }
-
-    This.resize(nChar);
-
-    return (nChar != maxLen);
-}
-
-
-fileName fileNameClean(fileName& This)
-{
-    fileName fName(This);
-    fileNameCleanThis(fName);
-
-    return fName;
-}
-
-
 void printCleaning(fileName& pathName)
 {
     Info<< "fileName = " << pathName << nl
         << "  path() = " << pathName.path() << nl
-        << "  name() = " << pathName.name() << nl << nl;
+        << "  name() = " << pathName.name() << nl
+        << "  joined = " << pathName.path()/pathName.name() << nl << nl;
 
-    fileNameCleanThis(pathName);
+    pathName.clean();
 
     Info<< "cleaned  = " << pathName << nl
         << "  path() = " << pathName.path() << nl
-        << "  name() = " << pathName.name() << nl << nl;
+        << "  name() = " << pathName.name() << nl
+        << "  joined = " << pathName.path()/pathName.name() << nl << nl;
 
     IOobject::writeDivider(Info);
 }
@@ -195,7 +77,14 @@ int main(int argc, char *argv[])
     if (args.optionFound("case"))
     {
         fileName pathName = args.option("case");
-        Info<< "-case\n";
+        Info<< nl
+            << "-case" << nl
+            << "path = " << args.path() << nl
+            << "root = " << args.rootPath() << nl
+            << "case = " << args.caseName() << nl
+            << "FOAM_CASE=" << getEnv("FOAM_CASE") << nl
+            << "FOAM_CASENAME=" << getEnv("FOAM_CASENAME") << nl
+            << endl;
 
         printCleaning(pathName);
     }
@@ -206,7 +95,6 @@ int main(int argc, char *argv[])
         printCleaning(pathName);
     }
 
-
     Info<< "\nEnd" << endl;
 
     return 0;
diff --git a/src/OpenFOAM/primitives/strings/fileName/fileName.C b/src/OpenFOAM/primitives/strings/fileName/fileName.C
index ac6dc75025..e157c15e34 100644
--- a/src/OpenFOAM/primitives/strings/fileName/fileName.C
+++ b/src/OpenFOAM/primitives/strings/fileName/fileName.C
@@ -55,18 +55,115 @@ Foam::fileName::Type Foam::fileName::type() const
 }
 
 
+//
+// * remove repeated slashes
+//       /abc////def        -->   /abc/def
+//
+// * remove '/./'
+//       /abc/def/./ghi/.   -->   /abc/def/./ghi
+//       abc/def/./         -->   abc/def
+//
+// * remove '/../'
+//       /abc/def/../ghi/jkl/nmo/..   -->   /abc/ghi/jkl
+//       abc/../def/ghi/../jkl        -->   abc/../def/jkl
+//
+// * remove trailing '/'
+//
 bool Foam::fileName::clean()
 {
-    bool changed = false;
+    // the top slash - we are never allowed to go above it
+    register string::size_type top = this->find('/');
 
-    changed = this->removeRepeated('/') || changed;
-    changed = this->removeTrailing('/') || changed;
+    // no slashes - nothing to do
+    if (top == string::npos)
+    {
+        return false;
+    }
 
-    return changed;
+    // start with the '/' found:
+    register char prev = '/';
+    register string::size_type nChar  = top+1;
+    register string::size_type maxLen = this->size();
+
+    for
+    (
+        register string::size_type src = nChar;
+        src < maxLen;
+        /*nil*/
+    )
+    {
+        register char c = operator[](src++);
+
+        if (prev == '/')
+        {
+            // repeated '/' - skip it
+            if (c == '/')
+            {
+                continue;
+            }
+
+            // could be '/./' or '/../'
+            if (c == '.')
+            {
+                // found trailing '/.' - skip it
+                if (src >= maxLen)
+                {
+                    continue;
+                }
+
+
+                // peek at the next character
+                register char c1 = operator[](src);
+
+                // found '/./' - skip it
+                if (c1 == '/')
+                {
+                    src++;
+                    continue;
+                }
+
+                // it is '/..' or '/../'
+                if (c1 == '.' && (src+1 >= maxLen || operator[](src+1) == '/'))
+                {
+                    string::size_type parent;
+
+                    // backtrack to find the parent directory
+                    // minimum of 3 characters:  '/x/../'
+                    // strip it, provided it is above the top point
+                    if
+                    (
+                        nChar > 2
+                     && (parent = this->rfind('/', nChar-2)) != string::npos
+                     && parent >= top
+                    )
+                    {
+                        nChar = parent + 1;   // retain '/' from the parent
+                        src += 2;
+                        continue;
+                    }
+
+                    // bad resolution, eg 'abc/../../'
+                    // retain the sequence, but move the top to avoid it being
+                    // considered a valid parent later
+                    top = nChar + 2;
+                }
+            }
+        }
+        operator[](nChar++) = prev = c;
+    }
+
+    // remove trailing slash
+    if (nChar > 1 && operator[](nChar-1) == '/')
+    {
+        nChar--;
+    }
+
+    this->resize(nChar);
+
+    return (nChar != maxLen);
 }
 
 
-// Return string with repeated characters removed
 Foam::fileName Foam::fileName::clean() const
 {
     fileName fName(*this);