Fix issue with output in parallel

(cherry picked from commit 78866c06)

library/LibUtilities/BasicUtils/FieldIO.cpp

@@ -1080,7 +1080,6 @@ namespace Nektar
             }
         }
 
-
         /**
          * \brief add information about provenance and fieldmetadata
          */
@@ -1277,6 +1276,14 @@ namespace Nektar
 
             m_comm->Block();
 
+            // Sit in a loop and make sure target directory has been created
+            int created = 0;
+            while (!created)
+            {
+                created = fs::is_directory(specPath);
+                m_comm->AllReduce(created, ReduceMin);
+            }
+
             // Return the full path to the partition for this process
             return LibUtilities::PortablePath(fulloutname);
         }