Purpose: Fix HDFFV-9532

Description:
    Removed obsolete macros from C++ API library and tests:
    H5_NO_NAMESPACE and __cplusplus
    Leave OLD_HEADER_FILENAME because iostream.h might still be in use,
    until further checking is done.
    Leave H5_NO_STD to consider retiring H5std_string first.
Platforms tested:
    Linux/32 2.6 (jam)
    Linux/64 (jelly)
    Darwin (osx1010test)

73 files changed, 14 insertions, 377 deletions

diff --git a/c++/src/H5AbstractDs.cpp b/c++/src/H5AbstractDs.cpp
index 51d5f88..e58bb03 100644
--- a/c++/src/H5AbstractDs.cpp
+++ b/c++/src/H5AbstractDs.cpp
@@ -27,9 +27,7 @@
 #include "H5CommonFG.h"
 #include "H5Alltypes.h"
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 //--------------------------------------------------------------------------
 // Function:	AbstractDs default constructor
@@ -324,6 +322,4 @@ VarLenType AbstractDs::getVarLenType() const
 //--------------------------------------------------------------------------
 AbstractDs::~AbstractDs() {}
 
-#ifndef H5_NO_NAMESPACE
 } // end namespace
-#endif
diff --git a/c++/src/H5AbstractDs.h b/c++/src/H5AbstractDs.h
index 6975d6f..1b4775c 100644
--- a/c++/src/H5AbstractDs.h
+++ b/c++/src/H5AbstractDs.h
@@ -17,9 +17,7 @@
 #ifndef __AbstractDs_H
 #define __AbstractDs_H
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 class ArrayType;
 class CompType;
@@ -94,7 +92,5 @@ class H5_DLLCPP AbstractDs {
 	// This member function is implemented by DataSet and Attribute - pure virtual.
 	virtual hid_t p_get_type() const = 0;
 };
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif // __AbstractDs_H
diff --git a/c++/src/H5ArrayType.cpp b/c++/src/H5ArrayType.cpp
index 02596a2..3df9c47 100644
--- a/c++/src/H5ArrayType.cpp
+++ b/c++/src/H5ArrayType.cpp
@@ -26,9 +26,7 @@
 #include "H5DataType.h"
 #include "H5ArrayType.h"
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 //--------------------------------------------------------------------------
 // Function:	ArrayType default constructor
@@ -154,6 +152,4 @@ int ArrayType::getArrayDims(hsize_t* dims) const
 //--------------------------------------------------------------------------
 ArrayType::~ArrayType() {}
 
-#ifndef H5_NO_NAMESPACE
 } // end namespace
-#endif
diff --git a/c++/src/H5ArrayType.h b/c++/src/H5ArrayType.h
index fb6c711..4407ba0 100644
--- a/c++/src/H5ArrayType.h
+++ b/c++/src/H5ArrayType.h
@@ -17,9 +17,7 @@
 #ifndef __H5ArrayType_H
 #define __H5ArrayType_H
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 /*! \class ArrayType
     \brief Class ArrayType inherits from DataType and provides wrappers for
@@ -57,7 +55,5 @@ class H5_DLLCPP ArrayType : public DataType {
 	// Default constructor
 	ArrayType();
 };
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif // __H5ArrayType_H
diff --git a/c++/src/H5AtomType.cpp b/c++/src/H5AtomType.cpp
index 90c2ae3..00922b1 100644
--- a/c++/src/H5AtomType.cpp
+++ b/c++/src/H5AtomType.cpp
@@ -26,9 +26,7 @@
 #include "H5DataType.h"
 #include "H5AtomType.h"
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 #ifndef DOXYGEN_SHOULD_SKIP_THIS
 //--------------------------------------------------------------------------
@@ -295,6 +293,4 @@ void AtomType::setPad( H5T_pad_t lsb, H5T_pad_t msb ) const
 AtomType::~AtomType() {}
 #endif // DOXYGEN_SHOULD_SKIP_THIS
 
-#ifndef H5_NO_NAMESPACE
 } // end namespace
-#endif
diff --git a/c++/src/H5AtomType.h b/c++/src/H5AtomType.h
index 792312a..9cfc6de 100644
--- a/c++/src/H5AtomType.h
+++ b/c++/src/H5AtomType.h
@@ -17,9 +17,7 @@
 #ifndef __H5AtomType_H
 #define __H5AtomType_H
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 /*! \class AtomType
     \brief AtomType is a base class, inherited by IntType, FloatType,
@@ -79,7 +77,5 @@ class H5_DLLCPP AtomType : public DataType {
 	AtomType( const hid_t existing_id );
 #endif // DOXYGEN_SHOULD_SKIP_THIS
 };
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif // __H5AtomType_H
diff --git a/c++/src/H5Attribute.cpp b/c++/src/H5Attribute.cpp
index b810624..1ba8c79 100644
--- a/c++/src/H5Attribute.cpp
+++ b/c++/src/H5Attribute.cpp
@@ -37,13 +37,11 @@
 #include "H5Attribute.h"
 #include "H5private.h"		// for HDfree
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
 #ifndef H5_NO_STD
     using std::cerr;
     using std::endl;
 #endif  // H5_NO_STD
-#endif
 
 class H5_DLLCPP H5Object;  // forward declaration for UserData4Aiterate
 
@@ -679,7 +677,4 @@ Attribute::~Attribute()
 	cerr << "Attribute::~Attribute - " << close_error.getDetailMsg() << endl;
     }
 }
-
-#ifndef H5_NO_NAMESPACE
 } // end namespace
-#endif
diff --git a/c++/src/H5Attribute.h b/c++/src/H5Attribute.h
index f5ee4a9..4a27add 100644
--- a/c++/src/H5Attribute.h
+++ b/c++/src/H5Attribute.h
@@ -17,9 +17,7 @@
 #ifndef __H5Attribute_H
 #define __H5Attribute_H
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 /*! \class Attribute
     \brief Class Attribute operates on HDF5 attributes.
@@ -115,7 +113,5 @@ class H5_DLLCPP Attribute : public AbstractDs, public IdComponent {
 	friend void f_Attribute_setId(Attribute* attr, hid_t new_id);
 
 };
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif // __H5Attribute_H
diff --git a/c++/src/H5Classes.h b/c++/src/H5Classes.h
index de7cf4a..e45c627 100644
--- a/c++/src/H5Classes.h
+++ b/c++/src/H5Classes.h
@@ -17,9 +17,7 @@
 #ifndef __H5Classes_H
 #define __H5Classes_H
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 	class Exception;
 	class IdComponent;
 	class H5Location;
@@ -46,7 +44,5 @@ namespace H5 {
 	class H5File;
 	class Attribute;
 	class H5Library;
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif // __H5Classes_H
diff --git a/c++/src/H5CommonFG.cpp b/c++/src/H5CommonFG.cpp
index 9d284c3..1f9f1f9 100644
--- a/c++/src/H5CommonFG.cpp
+++ b/c++/src/H5CommonFG.cpp
@@ -47,9 +47,7 @@
 //   GroupIException.
 // December 2000
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 //--------------------------------------------------------------------------
 // Function:	CommonFG::createGroup
@@ -1302,7 +1300,5 @@ void f_DataSet_setId(DataSet* dset, hid_t new_id)
 
 #endif // DOXYGEN_SHOULD_SKIP_THIS
 
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 
diff --git a/c++/src/H5CommonFG.h b/c++/src/H5CommonFG.h
index 9fee802..f700943 100644
--- a/c++/src/H5CommonFG.h
+++ b/c++/src/H5CommonFG.h
@@ -17,9 +17,7 @@
 #ifndef __CommonFG_H
 #define __CommonFG_H
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 // Class forwarding
 class Group;
@@ -173,8 +171,6 @@ class H5_DLLCPP CommonFG {
 
 }; // end of CommonFG declaration
 
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif // __CommonFG_H
 
diff --git a/c++/src/H5CompType.cpp b/c++/src/H5CompType.cpp
index 4585516..28ea281 100644
--- a/c++/src/H5CompType.cpp
+++ b/c++/src/H5CompType.cpp
@@ -30,9 +30,7 @@
 #include "H5DataSet.h"
 #include "H5private.h"
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 //--------------------------------------------------------------------------
 // Function:	CompType default constructor
@@ -485,6 +483,4 @@ void CompType::setSize(size_t size) const
 //--------------------------------------------------------------------------
 CompType::~CompType() {}
 
-#ifndef H5_NO_NAMESPACE
 } // end namespace
-#endif
diff --git a/c++/src/H5CompType.h b/c++/src/H5CompType.h
index bd6d76c..b651523 100644
--- a/c++/src/H5CompType.h
+++ b/c++/src/H5CompType.h
@@ -17,9 +17,7 @@
 #ifndef __H5CompType_H
 #define __H5CompType_H
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 /*! \class CompType
     \brief CompType is a derivative of a DataType and operates on HDF5
@@ -112,7 +110,5 @@ class H5_DLLCPP CompType : public DataType {
 	// getMemberXxxType
 	hid_t p_get_member_type(unsigned member_num) const;
 };
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif // __H5CompType_H
diff --git a/c++/src/H5DataSet.cpp b/c++/src/H5DataSet.cpp
index 8a42494..608ec5f 100644
--- a/c++/src/H5DataSet.cpp
+++ b/c++/src/H5DataSet.cpp
@@ -40,13 +40,11 @@
 #include "H5DataSet.h"
 #include "H5private.h"		// for HDfree
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
 #ifndef H5_NO_STD
     using std::cerr;
     using std::endl;
 #endif  // H5_NO_STD
-#endif
 
 //--------------------------------------------------------------------------
 // Function:	DataSet default constructor
@@ -851,7 +849,4 @@ DataSet::~DataSet()
 	cerr << "DataSet::~DataSet - " << close_error.getDetailMsg() << endl;
     }
 }
-
-#ifndef H5_NO_NAMESPACE
 } // end namespace
-#endif
diff --git a/c++/src/H5DataSet.h b/c++/src/H5DataSet.h
index dce21a5..e92118d 100644
--- a/c++/src/H5DataSet.h
+++ b/c++/src/H5DataSet.h
@@ -17,9 +17,7 @@
 #ifndef __H5DataSet_H
 #define __H5DataSet_H
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 /*! \class DataSet
     \brief Class DataSet operates on HDF5 datasets.
@@ -131,7 +129,5 @@ class H5_DLLCPP DataSet : public H5Object, public AbstractDs {
 	friend void f_DataSet_setId(DataSet* dset, hid_t new_id);
 
 };
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif // __H5DataSet_H
diff --git a/c++/src/H5DataSpace.cpp b/c++/src/H5DataSpace.cpp
index e10b841..1b18300 100644
--- a/c++/src/H5DataSpace.cpp
+++ b/c++/src/H5DataSpace.cpp
@@ -25,13 +25,11 @@
 #include "H5IdComponent.h"
 #include "H5DataSpace.h"
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
 #ifndef H5_NO_STD
     using std::cerr;
     using std::endl;
 #endif  // H5_NO_STD
-#endif
 
 #ifndef DOXYGEN_SHOULD_SKIP_THIS
 // This DOXYGEN_SHOULD_SKIP_THIS block is a work-around approach to control
@@ -707,7 +705,4 @@ DataSpace::~DataSpace()
 	cerr << "DataSpace::~DataSpace - " << close_error.getDetailMsg() << endl;
     }
 }
-
-#ifndef H5_NO_NAMESPACE
 } // end namespace
-#endif
diff --git a/c++/src/H5DataSpace.h b/c++/src/H5DataSpace.h
index 384f1a3..47fe168 100644
--- a/c++/src/H5DataSpace.h
+++ b/c++/src/H5DataSpace.h
@@ -17,9 +17,7 @@
 #ifndef __H5DataSpace_H
 #define __H5DataSpace_H
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 //! Class DataSpace operates on HDF5 dataspaces.
 class H5_DLLCPP DataSpace : public IdComponent {
@@ -147,7 +145,5 @@ class H5_DLLCPP DataSpace : public IdComponent {
 
 #endif // DOXYGEN_SHOULD_SKIP_THIS
 };
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif // __H5DataSpace_H
diff --git a/c++/src/H5DataType.cpp b/c++/src/H5DataType.cpp
index dab5637..52994ff 100644
--- a/c++/src/H5DataType.cpp
+++ b/c++/src/H5DataType.cpp
@@ -41,13 +41,11 @@
 #include "H5File.h"
 #include "H5Attribute.h"
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
 #ifndef H5_NO_STD
     using std::cerr;
     using std::endl;
 #endif  // H5_NO_STD
-#endif
 
 //--------------------------------------------------------------------------
 // Function:	DataType default constructor
@@ -780,6 +778,4 @@ DataType::~DataType()
 	cerr << inMemFunc("~DataType - ") << close_error.getDetailMsg() << endl;
     }
 }
-#ifndef H5_NO_NAMESPACE
 } // end namespace
-#endif
diff --git a/c++/src/H5DataType.h b/c++/src/H5DataType.h
index 7dd25ac..159e3fc 100644
--- a/c++/src/H5DataType.h
+++ b/c++/src/H5DataType.h
@@ -20,9 +20,7 @@
 #ifndef __H5DataType_H
 #define __H5DataType_H
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 /*! \class DataType
     \brief Class DataType provides generic operations on HDF5 datatypes.
@@ -144,7 +142,5 @@ class H5_DLLCPP DataType : public H5Object {
 
 	void p_commit(hid_t loc_id, const char* name);
 };
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif // __H5DataType_H
diff --git a/c++/src/H5DcreatProp.cpp b/c++/src/H5DcreatProp.cpp
index d362d65..61705cd 100644
--- a/c++/src/H5DcreatProp.cpp
+++ b/c++/src/H5DcreatProp.cpp
@@ -25,9 +25,7 @@
 #include "H5CommonFG.h"
 #include "H5DataType.h"
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 #ifndef DOXYGEN_SHOULD_SKIP_THIS
 // This DOXYGEN_SHOULD_SKIP_THIS block is a work-around approach to control
@@ -747,6 +745,4 @@ void DSetCreatPropList::getExternal( unsigned idx, size_t name_size, char* name,
 //--------------------------------------------------------------------------
 DSetCreatPropList::~DSetCreatPropList () {}
 
-#ifndef H5_NO_NAMESPACE
 } // end namespace
-#endif
diff --git a/c++/src/H5DcreatProp.h b/c++/src/H5DcreatProp.h
index fed41b4..fec13fd 100644
--- a/c++/src/H5DcreatProp.h
+++ b/c++/src/H5DcreatProp.h
@@ -20,9 +20,7 @@
 #ifndef __H5DSCreatPropList_H
 #define __H5DSCreatPropList_H
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 /*! \class DSetCreatPropList
     \brief Class DSetCreatPropList represents the dataset creation property
@@ -143,7 +141,5 @@ class H5_DLLCPP DSetCreatPropList : public ObjCreatPropList {
 
 #endif // DOXYGEN_SHOULD_SKIP_THIS
 };
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif // __H5DSCreatPropList_H
diff --git a/c++/src/H5DxferProp.cpp b/c++/src/H5DxferProp.cpp
index 74db9ef..c4886f0 100644
--- a/c++/src/H5DxferProp.cpp
+++ b/c++/src/H5DxferProp.cpp
@@ -22,9 +22,7 @@
 #include "H5DxferProp.h"
 #include "H5private.h"		// for HDmemset
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 #ifndef DOXYGEN_SHOULD_SKIP_THIS
 // This DOXYGEN_SHOULD_SKIP_THIS block is a work-around approach to control
@@ -566,7 +564,5 @@ H5Z_EDC_t DSetMemXferPropList::getEDCCheck() const
 //--------------------------------------------------------------------------
 DSetMemXferPropList::~DSetMemXferPropList() {}
 
-#ifndef H5_NO_NAMESPACE
 } // end namespace
-#endif
 
diff --git a/c++/src/H5DxferProp.h b/c++/src/H5DxferProp.h
index 31fc372..815a67f 100644
--- a/c++/src/H5DxferProp.h
+++ b/c++/src/H5DxferProp.h
@@ -20,9 +20,7 @@
 #ifndef __H5DSetMemXferPropList_H
 #define __H5DSetMemXferPropList_H
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 /*! \class DSetMemXferPropList
     \brief Class DSetMemXferPropList represents the dataset memory and
@@ -131,7 +129,5 @@ class H5_DLLCPP DSetMemXferPropList : public PropList {
 
 #endif // DOXYGEN_SHOULD_SKIP_THIS
 };
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif // __H5DSetMemXferPropList_H
diff --git a/c++/src/H5EnumType.cpp b/c++/src/H5EnumType.cpp
index b096a36..8677b47 100644
--- a/c++/src/H5EnumType.cpp
+++ b/c++/src/H5EnumType.cpp
@@ -33,9 +33,7 @@
 #include "H5EnumType.h"
 #include "H5private.h"			// for HDmemset
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 //--------------------------------------------------------------------------
 // Function:	EnumType default constructor
@@ -277,6 +275,4 @@ void EnumType::getMemberValue( unsigned memb_no, void *value ) const
 //--------------------------------------------------------------------------
 EnumType::~EnumType() {}
 
-#ifndef H5_NO_NAMESPACE
 } // end namespace
-#endif
diff --git a/c++/src/H5EnumType.h b/c++/src/H5EnumType.h
index fe36e8b..d4f42fb 100644
--- a/c++/src/H5EnumType.h
+++ b/c++/src/H5EnumType.h
@@ -17,9 +17,7 @@
 #ifndef __H5EnumType_H
 #define __H5EnumType_H
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 //! Class EnumType operates on HDF5 enum datatypes.
 class H5_DLLCPP EnumType : public DataType {
@@ -72,7 +70,5 @@ class H5_DLLCPP EnumType : public DataType {
 
 	virtual ~EnumType();
 };
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif // __H5EnumType_H
diff --git a/c++/src/H5Exception.cpp b/c++/src/H5Exception.cpp
index 9df861a..da42ca4 100644
--- a/c++/src/H5Exception.cpp
+++ b/c++/src/H5Exception.cpp
@@ -18,9 +18,7 @@
 #include "H5Include.h"
 #include "H5Exception.h"
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 const char Exception::DEFAULT_MSG[] = "No detailed information provided";
 
@@ -586,6 +584,4 @@ IdComponentException::IdComponentException(const H5std_string& func, const H5std
 ///\brief	Noop destructor.
 //--------------------------------------------------------------------------
 IdComponentException::~IdComponentException() throw() {}
-#ifndef H5_NO_NAMESPACE
 } // end namespace
-#endif
diff --git a/c++/src/H5Exception.h b/c++/src/H5Exception.h
index d49c19a..c64cf2a 100644
--- a/c++/src/H5Exception.h
+++ b/c++/src/H5Exception.h
@@ -19,14 +19,12 @@
 
 #include <string>
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
 #ifdef H5_NO_STD
     #define H5std_string ::string
 #else
     #define H5std_string std::string
 #endif
-#endif
 
 /*! \class Exception
     \brief Exception provides wrappers of HDF5 error handling functions.
@@ -170,9 +168,6 @@ class H5_DLLCPP IdComponentException : public Exception {
 	IdComponentException();
 	virtual ~IdComponentException() throw();
 };
-
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 
 #endif // __H5Exception_H
diff --git a/c++/src/H5FaccProp.cpp b/c++/src/H5FaccProp.cpp
index 1b05b02..a09cf55 100644
--- a/c++/src/H5FaccProp.cpp
+++ b/c++/src/H5FaccProp.cpp
@@ -21,9 +21,7 @@
 #include "H5PropList.h"
 #include "H5FaccProp.h"
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 #ifndef DOXYGEN_SHOULD_SKIP_THIS
 // This DOXYGEN_SHOULD_SKIP_THIS block is a work-around approach to control
@@ -752,6 +750,4 @@ void FileAccPropList::getLibverBounds(H5F_libver_t& libver_low, H5F_libver_t& li
 //--------------------------------------------------------------------------
 FileAccPropList::~FileAccPropList() {}
 
-#ifndef H5_NO_NAMESPACE
 } // end namespace
-#endif
diff --git a/c++/src/H5FaccProp.h b/c++/src/H5FaccProp.h
index 831488c..61dec04 100644
--- a/c++/src/H5FaccProp.h
+++ b/c++/src/H5FaccProp.h
@@ -20,9 +20,7 @@
 #ifndef __H5FileAccPropList_H
 #define __H5FileAccPropList_H
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 //! Class FileAccPropList represents the HDF5 file access property list.
 class H5_DLLCPP FileAccPropList : public PropList {
@@ -157,7 +155,5 @@ class H5_DLLCPP FileAccPropList : public PropList {
 #endif // DOXYGEN_SHOULD_SKIP_THIS
 
 };
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif // __H5FileAccPropList_H
diff --git a/c++/src/H5FcreatProp.cpp b/c++/src/H5FcreatProp.cpp
index 661c94b..cc4e26d 100644
--- a/c++/src/H5FcreatProp.cpp
+++ b/c++/src/H5FcreatProp.cpp
@@ -21,9 +21,7 @@
 #include "H5PropList.h"
 #include "H5FcreatProp.h"
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 #ifndef DOXYGEN_SHOULD_SKIP_THIS
 // This DOXYGEN_SHOULD_SKIP_THIS block is a work-around approach to control
@@ -301,6 +299,4 @@ unsigned FileCreatPropList::getIstorek() const
 //--------------------------------------------------------------------------
 FileCreatPropList::~FileCreatPropList() {}
 
-#ifndef H5_NO_NAMESPACE
 } // end namespace
-#endif
diff --git a/c++/src/H5FcreatProp.h b/c++/src/H5FcreatProp.h
index ae32134..fc43448 100644
--- a/c++/src/H5FcreatProp.h
+++ b/c++/src/H5FcreatProp.h
@@ -17,9 +17,7 @@
 #ifndef __H5FileCreatPropList_H
 #define __H5FileCreatPropList_H
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 //! Class FileCreatPropList represents the HDF5 file create property list.
 class H5_DLLCPP FileCreatPropList : public PropList {
@@ -87,7 +85,5 @@ class H5_DLLCPP FileCreatPropList : public PropList {
 #endif // DOXYGEN_SHOULD_SKIP_THIS
 
 };
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif // __H5FileCreatPropList_H
diff --git a/c++/src/H5File.cpp b/c++/src/H5File.cpp
index 1b13af0..d1b7b06 100644
--- a/c++/src/H5File.cpp
+++ b/c++/src/H5File.cpp
@@ -38,13 +38,11 @@
 #include "H5File.h"
 #include "H5Alltypes.h"
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
 #ifndef H5_NO_STD
     using std::cerr;
     using std::endl;
 #endif  // H5_NO_STD
-#endif
 
 //--------------------------------------------------------------------------
 // Function	H5File default constructor
@@ -658,6 +656,4 @@ H5File::~H5File()
     }
 }
 
-#ifndef H5_NO_NAMESPACE
 } // end namespace
-#endif
diff --git a/c++/src/H5File.h b/c++/src/H5File.h
index 7f271da..063a94e 100644
--- a/c++/src/H5File.h
+++ b/c++/src/H5File.h
@@ -17,9 +17,7 @@
 #ifndef __H5File_H
 #define __H5File_H
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 /*! \class H5File
     \brief Class H5File represents an HDF5 file.
@@ -121,7 +119,5 @@ class H5_DLLCPP H5File : public H5Location, public CommonFG {
 	void p_get_file( const char* name, unsigned int flags, const FileCreatPropList& create_plist, const FileAccPropList& access_plist );
 
 };
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif // __H5File_H
diff --git a/c++/src/H5FloatType.cpp b/c++/src/H5FloatType.cpp
index cdf9872..b1b2ce2 100644
--- a/c++/src/H5FloatType.cpp
+++ b/c++/src/H5FloatType.cpp
@@ -32,9 +32,7 @@
 #include "H5DataSet.h"
 #include "H5PredType.h"
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 //--------------------------------------------------------------------------
 // Function:	FloatType default constructor
@@ -285,6 +283,4 @@ void FloatType::setInpad( H5T_pad_t inpad ) const
 //--------------------------------------------------------------------------
 FloatType::~FloatType() {}
 
-#ifndef H5_NO_NAMESPACE
 } // end namespace
-#endif
diff --git a/c++/src/H5FloatType.h b/c++/src/H5FloatType.h
index e88093e..201760b 100644
--- a/c++/src/H5FloatType.h
+++ b/c++/src/H5FloatType.h
@@ -17,9 +17,7 @@
 #ifndef __H5FloatType_H
 #define __H5FloatType_H
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 //! Class FloatType operates on HDF5 floating point datatype.
 class H5_DLLCPP FloatType : public AtomType {
@@ -69,7 +67,5 @@ class H5_DLLCPP FloatType : public AtomType {
 	// Noop destructor.
 	virtual ~FloatType();
 };
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif // __H5FloatType_H
diff --git a/c++/src/H5Group.cpp b/c++/src/H5Group.cpp
index 0f2ff04..4cf7b98 100644
--- a/c++/src/H5Group.cpp
+++ b/c++/src/H5Group.cpp
@@ -39,13 +39,11 @@
 #include "H5File.h"
 #include "H5Alltypes.h"
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
 #ifndef H5_NO_STD
     using std::cerr;
     using std::endl;
 #endif  // H5_NO_STD
-#endif
 
 //--------------------------------------------------------------------------
 // Function:	Group default constructor
@@ -224,6 +222,4 @@ Group::~Group()
     }
 }
 
-#ifndef H5_NO_NAMESPACE
 } // end namespace
-#endif
diff --git a/c++/src/H5Group.h b/c++/src/H5Group.h
index 100b214..474f72b 100644
--- a/c++/src/H5Group.h
+++ b/c++/src/H5Group.h
@@ -17,9 +17,7 @@
 #ifndef __H5Group_H
 #define __H5Group_H
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 /*! \class Group
     \brief Class Group represents an HDF5 group.
@@ -69,7 +67,5 @@ class H5_DLLCPP Group : public H5Object, public CommonFG {
 	hid_t id;	// HDF5 group id
 
 };
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif // __H5Group_H
diff --git a/c++/src/H5IdComponent.cpp b/c++/src/H5IdComponent.cpp
index 6d0c39f..d869b07 100644
--- a/c++/src/H5IdComponent.cpp
+++ b/c++/src/H5IdComponent.cpp
@@ -22,9 +22,7 @@
 #include "H5DataSpace.h"
 #include "H5private.h"			// for HDmemset
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 // This flag indicates whether H5Library::initH5cpp has been called to register
 // the terminating functions with atexit()
@@ -352,6 +350,4 @@ bool IdComponent::p_valid_id(const hid_t obj_id)
 
 #endif // DOXYGEN_SHOULD_SKIP_THIS
 
-#ifndef H5_NO_NAMESPACE
 }
-#endif
diff --git a/c++/src/H5IdComponent.h b/c++/src/H5IdComponent.h
index 34f2da8..cf19dc6 100644
--- a/c++/src/H5IdComponent.h
+++ b/c++/src/H5IdComponent.h
@@ -19,9 +19,7 @@
 
 // IdComponent represents an HDF5 object that has an identifier.
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 class DataSpace;
 /*! \class IdComponent
@@ -121,7 +119,5 @@ class H5_DLLCPP IdComponent {
 
 }; // end class IdComponent
 
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif // __IdComponent_H
diff --git a/c++/src/H5IntType.cpp b/c++/src/H5IntType.cpp
index 5719eed..fd35673 100644
--- a/c++/src/H5IntType.cpp
+++ b/c++/src/H5IntType.cpp
@@ -32,9 +32,7 @@
 #include "H5DataSet.h"
 #include "H5PredType.h"
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 
 //--------------------------------------------------------------------------
@@ -136,6 +134,4 @@ void IntType::setSign( H5T_sign_t sign ) const
 //--------------------------------------------------------------------------
 IntType::~IntType() {}
 
-#ifndef H5_NO_NAMESPACE
 } // end namespace
-#endif
diff --git a/c++/src/H5IntType.h b/c++/src/H5IntType.h
index e28f5c2..afe7a67 100644
--- a/c++/src/H5IntType.h
+++ b/c++/src/H5IntType.h
@@ -17,9 +17,7 @@
 #ifndef __H5IntType_H
 #define __H5IntType_H
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 //! Class IntType operates on HDF5 integer datatype.
 class H5_DLLCPP IntType : public AtomType {
@@ -51,7 +49,5 @@ class H5_DLLCPP IntType : public AtomType {
 	// Noop destructor.
 	virtual ~IntType();
 };
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif // __H5IntType_H
diff --git a/c++/src/H5Library.cpp b/c++/src/H5Library.cpp
index 471dbad..65f1f00 100644
--- a/c++/src/H5Library.cpp
+++ b/c++/src/H5Library.cpp
@@ -33,9 +33,7 @@
 #include "H5DataSpace.h"
 #include "H5Library.h"
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 //--------------------------------------------------------------------------
 // Function:	H5Library::open (static)
@@ -260,6 +258,4 @@ H5Library::H5Library(){}
 // Destructor - private
 H5Library::~H5Library(){}
 
-#ifndef H5_NO_NAMESPACE
 } // end namespace
-#endif
diff --git a/c++/src/H5Library.h b/c++/src/H5Library.h
index 308881b..694b052 100644
--- a/c++/src/H5Library.h
+++ b/c++/src/H5Library.h
@@ -17,9 +17,7 @@
 #ifndef __H5Library_H
 #define __H5Library_H
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 /*! \class H5Library
     \brief Class H5Library operates the HDF5 library globably.
@@ -72,7 +70,5 @@ class H5_DLLCPP H5Library {
 #endif // DOXYGEN_SHOULD_SKIP_THIS
 
 };
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif // __H5Library_H
diff --git a/c++/src/H5Location.cpp b/c++/src/H5Location.cpp
index 0195fb8..96c7992 100644
--- a/c++/src/H5Location.cpp
+++ b/c++/src/H5Location.cpp
@@ -35,9 +35,7 @@
 #include "H5Attribute.h"
 #include "H5private.h"		// for HDmemset
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 #ifndef DOXYGEN_SHOULD_SKIP_THIS
 // userAttrOpWrpr simply interfaces between the user's function and the
@@ -959,6 +957,4 @@ void f_DataSpace_setId(DataSpace* dspace, hid_t new_id)
     dspace->p_setId(new_id);
 }
 
-#ifndef H5_NO_NAMESPACE
 } // end namespace
-#endif
diff --git a/c++/src/H5Location.h b/c++/src/H5Location.h
index 37571c5..a57f7f1 100644
--- a/c++/src/H5Location.h
+++ b/c++/src/H5Location.h
@@ -19,9 +19,7 @@
 
 #include "H5Classes.h"		// constains forward class declarations
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 class H5_DLLCPP H5Location;  // forward declaration for UserData4Aiterate
 
@@ -173,7 +171,5 @@ class H5_DLLCPP H5Location : public IdComponent {
 
 }; /* end class H5Location */
 
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif // __H5Location_H
diff --git a/c++/src/H5Object.cpp b/c++/src/H5Object.cpp
index f9d5abf..6bcc666 100644
--- a/c++/src/H5Object.cpp
+++ b/c++/src/H5Object.cpp
@@ -34,9 +34,7 @@
 #include "H5Attribute.h"
 #include "H5private.h"		// for HDmemset
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 #ifndef DOXYGEN_SHOULD_SKIP_THIS
 //--------------------------------------------------------------------------
@@ -192,6 +190,4 @@ ssize_t H5Object::getObjName(H5std_string& obj_name, size_t len) const
 H5Object::~H5Object() {}
 #endif // DOXYGEN_SHOULD_SKIP_THIS
 
-#ifndef H5_NO_NAMESPACE
 } // end namespace
-#endif
diff --git a/c++/src/H5Object.h b/c++/src/H5Object.h
index 193e5d1..cbeefc3 100644
--- a/c++/src/H5Object.h
+++ b/c++/src/H5Object.h
@@ -34,9 +34,7 @@
 //		to H5Location will risk breaking user applications.
 //		-BMR
 //	Apr 2, 2014: Added wrapper getObjName for H5Iget_name 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 /*! \class H5Object
     \brief Class H5Object is a bridge between H5Location and DataSet, DataType,
@@ -77,7 +75,5 @@ class H5_DLLCPP H5Object : public H5Location {
 
 }; /* end class H5Object */
 
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif // __H5Object_H
diff --git a/c++/src/H5OcreatProp.cpp b/c++/src/H5OcreatProp.cpp
index ca0e59e..18aa886 100644
--- a/c++/src/H5OcreatProp.cpp
+++ b/c++/src/H5OcreatProp.cpp
@@ -22,9 +22,7 @@
 #include "H5FaccProp.h"
 #include "H5OcreatProp.h"
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 #ifndef DOXYGEN_SHOULD_SKIP_THIS
 // This DOXYGEN_SHOULD_SKIP_THIS block is a work-around approach to control
@@ -216,6 +214,4 @@ unsigned ObjCreatPropList::getAttrCrtOrder() const
 //--------------------------------------------------------------------------
 ObjCreatPropList::~ObjCreatPropList() {}
 
-#ifndef H5_NO_NAMESPACE
 } // end namespace
-#endif
diff --git a/c++/src/H5OcreatProp.h b/c++/src/H5OcreatProp.h
index 0fda34d..823f747 100644
--- a/c++/src/H5OcreatProp.h
+++ b/c++/src/H5OcreatProp.h
@@ -17,9 +17,7 @@
 #ifndef __H5ObjCreatPropList_H
 #define __H5ObjCreatPropList_H
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 //! Class ObjCreatPropList represents the HDF5 object creation property list.
 class H5_DLLCPP ObjCreatPropList : public PropList {
@@ -70,7 +68,5 @@ class H5_DLLCPP ObjCreatPropList : public PropList {
 #endif // DOXYGEN_SHOULD_SKIP_THIS
 
 };
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif // __H5ObjCreatPropList_H
diff --git a/c++/src/H5PredType.cpp b/c++/src/H5PredType.cpp
index fb29f1e..2ff2f99 100644
--- a/c++/src/H5PredType.cpp
+++ b/c++/src/H5PredType.cpp
@@ -24,9 +24,7 @@
 #include "H5AtomType.h"
 #include "H5PredType.h"
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 #ifndef DOXYGEN_SHOULD_SKIP_THIS
 //--------------------------------------------------------------------------
@@ -886,9 +884,7 @@ const PredType& PredType::NATIVE_UINT_FAST64 = *NATIVE_UINT_FAST64_;
 
 #endif // DOXYGEN_SHOULD_SKIP_THIS
 
-#ifndef H5_NO_NAMESPACE
 } // end namespace
-#endif
 
 /***************************************************************************
 				Design Note
diff --git a/c++/src/H5PredType.h b/c++/src/H5PredType.h
index f560765..e0777f7 100644
--- a/c++/src/H5PredType.h
+++ b/c++/src/H5PredType.h
@@ -17,9 +17,7 @@
 #ifndef __H5PredType_H
 #define __H5PredType_H
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 /*! \class PredType
     \brief Class PredType holds the definition of all the HDF5 predefined
@@ -439,7 +437,5 @@ class H5_DLLCPP PredType : public AtomType {
 #endif // DOXYGEN_SHOULD_SKIP_THIS
 
 };
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif // __H5PredType_H
diff --git a/c++/src/H5PropList.cpp b/c++/src/H5PropList.cpp
index 6655900..def5693 100644
--- a/c++/src/H5PropList.cpp
+++ b/c++/src/H5PropList.cpp
@@ -28,13 +28,11 @@
 #include "H5private.h"		// for HDfree
 
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
 #ifndef H5_NO_STD
     using std::cerr;
     using std::endl;
 #endif  // H5_NO_STD
-#endif
 
 #ifndef DOXYGEN_SHOULD_SKIP_THIS
 // This DOXYGEN_SHOULD_SKIP_THIS block is a work-around approach to control
@@ -751,7 +749,4 @@ PropList::~PropList()
 	cerr << "PropList::~PropList - " << close_error.getDetailMsg() << endl;
     }
 }
-
-#ifndef H5_NO_NAMESPACE
 } // end namespace
-#endif
diff --git a/c++/src/H5PropList.h b/c++/src/H5PropList.h
index 7f6ee31..4161a1f 100644
--- a/c++/src/H5PropList.h
+++ b/c++/src/H5PropList.h
@@ -17,9 +17,7 @@
 #ifndef __H5PropList_H
 #define __H5PropList_H
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 //! Class PropList provides operations for generic property lists.
 class H5_DLLCPP PropList : public IdComponent {
@@ -133,7 +131,5 @@ class H5_DLLCPP PropList : public IdComponent {
 #endif // DOXYGEN_SHOULD_SKIP_THIS
 };
 
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif  // __H5PropList_H
diff --git a/c++/src/H5StrType.cpp b/c++/src/H5StrType.cpp
index 3cfa342..f18fa1e 100644
--- a/c++/src/H5StrType.cpp
+++ b/c++/src/H5StrType.cpp
@@ -32,9 +32,7 @@
 #include "H5DataSet.h"
 #include "H5PredType.h"
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 //--------------------------------------------------------------------------
 // Function:	StrType default constructor
@@ -247,6 +245,4 @@ void StrType::setStrpad( H5T_str_t strpad ) const
 //--------------------------------------------------------------------------
 StrType::~StrType() {}
 
-#ifndef H5_NO_NAMESPACE
 } // end namespace
-#endif
diff --git a/c++/src/H5StrType.h b/c++/src/H5StrType.h
index 8b3a773..4015998 100644
--- a/c++/src/H5StrType.h
+++ b/c++/src/H5StrType.h
@@ -17,9 +17,7 @@
 #ifndef __H5StrType_H
 #define __H5StrType_H
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 //! Class StrType operates on HDF5 string datatypes.
 class H5_DLLCPP StrType : public AtomType {
@@ -63,7 +61,5 @@ class H5_DLLCPP StrType : public AtomType {
 	// Noop destructor.
 	virtual ~StrType();
 };
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif // __H5StrType_H
diff --git a/c++/src/H5VarLenType.cpp b/c++/src/H5VarLenType.cpp
index 2fab1f3..db80a5a 100644
--- a/c++/src/H5VarLenType.cpp
+++ b/c++/src/H5VarLenType.cpp
@@ -26,9 +26,7 @@
 #include "H5DataType.h"
 #include "H5VarLenType.h"
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 
 //--------------------------------------------------------------------------
@@ -81,6 +79,4 @@ VarLenType::VarLenType(const DataType* base_type) : DataType()
 //--------------------------------------------------------------------------
 VarLenType::~VarLenType() {}
 
-#ifndef H5_NO_NAMESPACE
 } // end namespace
-#endif
diff --git a/c++/src/H5VarLenType.h b/c++/src/H5VarLenType.h
index 0a67d12..ca85f54 100644
--- a/c++/src/H5VarLenType.h
+++ b/c++/src/H5VarLenType.h
@@ -20,9 +20,7 @@
 #ifndef __H5VarLenType_H
 #define __H5VarLenType_H
 
-#ifndef H5_NO_NAMESPACE
 namespace H5 {
-#endif
 
 //! VarLenType operates on the HDF5 C's Variable-length Datatypes.
 class H5_DLLCPP VarLenType : public DataType {
@@ -46,7 +44,5 @@ class H5_DLLCPP VarLenType : public DataType {
 	// Default constructor
 	VarLenType();
 };
-#ifndef H5_NO_NAMESPACE
 }
-#endif
 #endif // __H5VarLenType_H
diff --git a/c++/test/dsets.cpp b/c++/test/dsets.cpp
index 7dcda0d..a9191d1 100644
--- a/c++/test/dsets.cpp
+++ b/c++/test/dsets.cpp
@@ -32,18 +32,14 @@
 #endif
 #include <string>
 
-#ifndef H5_NO_NAMESPACE
 #ifndef H5_NO_STD
     using std::cerr;
     using std::endl;
 #endif  // H5_NO_STD
-#endif
 
 #include "H5Cpp.h"	// C++ API header file
 
-#ifndef H5_NO_NAMESPACE
     using namespace H5;
-#endif
 
 #include "h5cpputil.h"	// C++ utilility header file
 
@@ -1175,9 +1171,7 @@ test_types(H5File& file)
  *
  *-------------------------------------------------------------------------
  */
-#ifdef __cplusplus
 extern "C"
-#endif
 void test_dset()
 {
     hid_t	fapl_id;
@@ -1235,9 +1229,7 @@ void test_dset()
  *
  *-------------------------------------------------------------------------
  */
-#ifdef __cplusplus
 extern "C"
-#endif
 void cleanup_dsets()
 {
     HDremove(FILE1.c_str());
diff --git a/c++/test/h5cpputil.cpp b/c++/test/h5cpputil.cpp
index f56782f..60dbf6c 100644
--- a/c++/test/h5cpputil.cpp
+++ b/c++/test/h5cpputil.cpp
@@ -28,19 +28,14 @@
 #endif
 #include <string>
 
-#ifndef H5_NO_NAMESPACE
 #ifndef H5_NO_STD
     using std::cerr;
     using std::endl;
 #endif  // H5_NO_STD
-#endif
 
 #include "h5test.h"
 #include "H5Cpp.h"
-
-#ifndef H5_NO_NAMESPACE
-    using namespace H5;
-#endif
+using namespace H5;
 
 #include "h5cpputil.h"
 
diff --git a/c++/test/h5cpputil.h b/c++/test/h5cpputil.h
index b615194..ede6850 100644
--- a/c++/test/h5cpputil.h
+++ b/c++/test/h5cpputil.h
@@ -26,9 +26,7 @@
 
 #include "h5test.h"
 
-#ifndef H5_NO_NAMESPACE
 using namespace H5;
-#endif
 
 #ifndef H5_NO_STD
 using std::cerr;
@@ -129,9 +127,7 @@ template <class Type1, class Type2>
 
 
 /* Prototypes for the test routines */
-#ifdef __cplusplus
 extern "C" {
-#endif
 void test_array();
 void test_attr();
 void test_compound();
@@ -161,9 +157,7 @@ void cleanup_reference();
 void cleanup_types();
 void cleanup_vlstrings();
 
-#ifdef __cplusplus
 }
-#endif
 
 /* not yet
 void cleanup_select(void);
diff --git a/c++/test/tarray.cpp b/c++/test/tarray.cpp
index 441ef81..1da9e0c 100644
--- a/c++/test/tarray.cpp
+++ b/c++/test/tarray.cpp
@@ -26,18 +26,13 @@
 #endif
 #include <string>
 
-#ifndef H5_NO_NAMESPACE
 #ifndef H5_NO_STD
     using std::cerr;
     using std::endl;
 #endif  // H5_NO_STD
-#endif
 
 #include "H5Cpp.h"      // C++ API header file
-
-#ifndef H5_NO_NAMESPACE
-    using namespace H5;
-#endif
+using namespace H5;
 
 #include "h5cpputil.h"  // C++ utilility header file
 
@@ -478,9 +473,7 @@ static void test_array_info()
 **  test_array(): Main datatypes testing routine.
 **
 ****************************************************************/
-#ifdef __cplusplus
 extern "C"
-#endif
 void test_array()
 {
     // Output message about test being performed
@@ -512,9 +505,7 @@ void test_array()
  *
  *-------------------------------------------------------------------------
  */
-#ifdef __cplusplus
 extern "C"
-#endif
 void cleanup_array()
 {
     HDremove(FILENAME.c_str());
diff --git a/c++/test/tattr.cpp b/c++/test/tattr.cpp
index d20466e..a739618 100644
--- a/c++/test/tattr.cpp
+++ b/c++/test/tattr.cpp
@@ -27,18 +27,13 @@
 #endif
 #include <string>
 
-#ifndef H5_NO_NAMESPACE
 #ifndef H5_NO_STD
     using std::cerr;
     using std::endl;
 #endif  // H5_NO_STD
-#endif
 
 #include "H5Cpp.h"	// C++ API header file
-
-#ifndef H5_NO_NAMESPACE
-    using namespace H5;
-#endif
+using namespace H5;
 
 #include "h5cpputil.h"	// C++ utilility header file
 
@@ -1783,9 +1778,7 @@ static void test_attr_corder_create_basic(FileCreatPropList& fcpl,
 **  test_attr(): Main attribute testing routine.
 **
 ****************************************************************/
-#ifdef __cplusplus
 extern "C"
-#endif
 void test_attr()
 {
     // Output message about test being performed
@@ -1883,9 +1876,7 @@ void test_attr()
  *
  *-------------------------------------------------------------------------
  */
-#ifdef __cplusplus
 extern "C"
-#endif
 void cleanup_attr()
 {
     HDremove(FILE_BASIC.c_str());
diff --git a/c++/test/tcompound.cpp b/c++/test/tcompound.cpp
index e293ded..c334e28 100644
--- a/c++/test/tcompound.cpp
+++ b/c++/test/tcompound.cpp
@@ -26,18 +26,13 @@
 #endif
 #include <string>
 
-#ifndef H5_NO_NAMESPACE
 #ifndef H5_NO_STD
     using std::cerr;
     using std::endl;
 #endif  // H5_NO_STD
-#endif
 
 #include "H5Cpp.h"      // C++ API header file
-
-#ifndef H5_NO_NAMESPACE
-    using namespace H5;
-#endif
+using namespace H5;
 
 #include "h5cpputil.h"  // C++ utilility header file
 
@@ -832,9 +827,7 @@ static void test_compound_set_size()
  *
  *-------------------------------------------------------------------------
  */
-#ifdef __cplusplus
 extern "C"
-#endif
 void test_compound()
 {
     // Output message about test being performed
@@ -863,9 +856,7 @@ void test_compound()
  *
  *-------------------------------------------------------------------------
  */
-#ifdef __cplusplus
 extern "C"
-#endif
 void cleanup_compound()
 {
     HDremove(COMPFILE.c_str());
diff --git a/c++/test/tdspl.cpp b/c++/test/tdspl.cpp
index ab93c26..3c04b67 100644
--- a/c++/test/tdspl.cpp
+++ b/c++/test/tdspl.cpp
@@ -27,18 +27,13 @@
 #endif
 #include <string>
 
-#ifndef H5_NO_NAMESPACE
 #ifndef H5_NO_STD
     using std::cerr;
     using std::endl;
 #endif  // H5_NO_STD
-#endif
 
 #include "H5Cpp.h"      // C++ API header file
-
-#ifndef H5_NO_NAMESPACE
-    using namespace H5;
-#endif
+using namespace H5;
 
 #include "h5cpputil.h"  // C++ utilility header file
 
@@ -126,9 +121,7 @@ static void test_transfplist()
 **  test_dsproplist(): Main dataset property list testing routine.
 **
 ****************************************************************/
-#ifdef __cplusplus
 extern "C"
-#endif
 void test_dsproplist()
 {
     // Output message about test being performed
@@ -139,9 +132,7 @@ void test_dsproplist()
 }   // test_dsproplist()
 
 
-#ifdef __cplusplus
 extern "C"
-#endif
 void cleanup_dsproplist()
 {
     HDremove(FILENAME.c_str());
diff --git a/c++/test/testhdf5.cpp b/c++/test/testhdf5.cpp
index dbf7e3e..21a5a7d 100644
--- a/c++/test/testhdf5.cpp
+++ b/c++/test/testhdf5.cpp
@@ -48,19 +48,14 @@
 #endif
 #include <string>
 
-#ifndef H5_NO_NAMESPACE
 #ifndef H5_NO_STD
     using std::cerr;
     using std::endl;
 #endif  // H5_NO_STD
-#endif
 
 #include "h5test.h"	// C test header file
 #include "H5Cpp.h"	// C++ API header file
-
-#ifndef H5_NO_NAMESPACE
-    using namespace H5;
-#endif  /* !H5_NO_NAMESPACE */
+using namespace H5;
 
 #include "h5cpputil.h"  // C++ utilility header file
 
diff --git a/c++/test/tfile.cpp b/c++/test/tfile.cpp
index b40b34c..11cc33e 100644
--- a/c++/test/tfile.cpp
+++ b/c++/test/tfile.cpp
@@ -30,18 +30,13 @@
 #endif
 #include <string>
 
-#ifndef H5_NO_NAMESPACE
 #ifndef H5_NO_STD
     using std::cerr;
     using std::endl;
 #endif  // H5_NO_STD
-#endif
 
 #include "H5Cpp.h"	// C++ API header file
-
-#ifndef H5_NO_NAMESPACE
-    using namespace H5;
-#endif
+using namespace H5;
 
 #include "h5cpputil.h"	// C++ utilility header file
 
@@ -755,9 +750,7 @@ static void test_libver_bounds()
  *
  *-------------------------------------------------------------------------
  */
-#ifdef __cplusplus
 extern "C"
-#endif
 void test_file()
 {
     // Output message about test being performed
@@ -785,9 +778,7 @@ void test_file()
  *
  *-------------------------------------------------------------------------
  */
-#ifdef __cplusplus
 extern "C"
-#endif
 void cleanup_file()
 {
     HDremove(FILE1.c_str());
diff --git a/c++/test/tfilter.cpp b/c++/test/tfilter.cpp
index 19549b3..101ec07 100644
--- a/c++/test/tfilter.cpp
+++ b/c++/test/tfilter.cpp
@@ -26,18 +26,13 @@
 #endif
 #include <string>
 
-#ifndef H5_NO_NAMESPACE
 #ifndef H5_NO_STD
     using std::cerr;
     using std::endl;
 #endif  // H5_NO_STD
-#endif
 
 #include "H5Cpp.h"      // C++ API header file
-
-#ifndef H5_NO_NAMESPACE
-    using namespace H5;
-#endif
+using namespace H5;
 
 #include "h5cpputil.h"  // C++ utilility header file
 
@@ -258,9 +253,7 @@ static void test_szip_filter(H5File& file1)
 **
 ****************************************************************/
 const H5std_string      FILE1("tfilters.h5");
-#ifdef __cplusplus
 extern "C"
-#endif
 void test_filters()
 {
     // Output message about test being performed
@@ -300,9 +293,7 @@ void test_filters()
  *
  *-------------------------------------------------------------------------
  */
-#ifdef __cplusplus
 extern "C"
-#endif
 void cleanup_filters()
 {
     HDremove(FILE1.c_str());
diff --git a/c++/test/th5s.cpp b/c++/test/th5s.cpp
index 7ef048b..16d1c57 100644
--- a/c++/test/th5s.cpp
+++ b/c++/test/th5s.cpp
@@ -29,18 +29,13 @@
 #endif
 #include <string>
 
-#ifndef H5_NO_NAMESPACE
 #ifndef H5_NO_STD
     using std::cerr;
     using std::endl;
 #endif  // H5_NO_STD
-#endif
 
 #include "H5Cpp.h"	// C++ API header file
-
-#ifndef H5_NO_NAMESPACE
-    using namespace H5;
-#endif
+using namespace H5;
 
 #include "h5cpputil.h"	// C++ utilility header file
 #include "H5srcdir.h"	// srcdir querying header file
@@ -566,9 +561,7 @@ static void test_h5s_compound_scalar_read()
  * Modifications:
  *-------------------------------------------------------------------------
  */
-#ifdef __cplusplus
 extern "C"
-#endif
 void test_h5s()
 {
     // Output message about test being performed
@@ -597,9 +590,7 @@ void test_h5s()
  *
  *-------------------------------------------------------------------------
  */
-#ifdef __cplusplus
 extern "C"
-#endif
 void cleanup_h5s()
 {
     HDremove(DATAFILE.c_str());
diff --git a/c++/test/tlinks.cpp b/c++/test/tlinks.cpp
index 025fedc..2b05764 100644
--- a/c++/test/tlinks.cpp
+++ b/c++/test/tlinks.cpp
@@ -26,18 +26,13 @@
 #endif
 #include <string>
 
-#ifndef H5_NO_NAMESPACE
 #ifndef H5_NO_STD
     using std::cerr;
     using std::endl;
 #endif  // H5_NO_STD
-#endif
 
 #include "H5Cpp.h"      // C++ API header file
-
-#ifndef H5_NO_NAMESPACE
-    using namespace H5;
-#endif
+using namespace H5;
 
 #include "h5cpputil.h"  // C++ test utilility header file
 
@@ -460,9 +455,7 @@ static void test_basic_links(hid_t fapl_id, hbool_t new_format)
  *
  *-------------------------------------------------------------------------
  */
-#ifdef __cplusplus
 extern "C"
-#endif
 void test_links()
 {
     hid_t	fapl_id, fapl2_id;    /* File access property lists */
@@ -651,9 +644,7 @@ void test_links()
  *
  *-------------------------------------------------------------------------
  */
-#ifdef __cplusplus
 extern "C"
-#endif
 void cleanup_links()
 {
     HDremove(FILENAME[0]);
diff --git a/c++/test/tobject.cpp b/c++/test/tobject.cpp
index 046e67a..aa6baf3 100644
--- a/c++/test/tobject.cpp
+++ b/c++/test/tobject.cpp
@@ -26,18 +26,13 @@
 #endif
 #include <string>
 
-#ifndef H5_NO_NAMESPACE
 #ifndef H5_NO_STD
     using std::cerr;
     using std::endl;
 #endif  // H5_NO_STD
-#endif
 
 #include "H5Cpp.h"      // C++ API header file
-
-#ifndef H5_NO_NAMESPACE
-    using namespace H5;
-#endif
+using namespace H5;
 
 #include "h5cpputil.h"  // C++ utilility header file
 
@@ -319,9 +314,7 @@ static void test_get_objtype()
  *
  *-------------------------------------------------------------------------
  */
-#ifdef __cplusplus
 extern "C"
-#endif
 void test_object()
 {
     // Output message about test being performed
@@ -346,9 +339,7 @@ void test_object()
  *
  *-------------------------------------------------------------------------
  */
-#ifdef __cplusplus
 extern "C"
-#endif
 void cleanup_object()
 {
     HDremove(FILE_OBJECTS.c_str());
diff --git a/c++/test/trefer.cpp b/c++/test/trefer.cpp
index d7c237f..e3499aa 100644
--- a/c++/test/trefer.cpp
+++ b/c++/test/trefer.cpp
@@ -28,10 +28,7 @@
 #include <string>
 
 #include "H5Cpp.h"      // C++ API header file
-
-#ifndef H5_NO_NAMESPACE
-    using namespace H5;
-#endif
+using namespace H5;
 
 #include "h5cpputil.h"  // C++ utilility header file
 
@@ -806,9 +803,7 @@ static void test_reference_compat(void)
 **  test_reference(): Main reference testing routine.
 **
 ****************************************************************/
-#ifdef __cplusplus
 extern "C"
-#endif
 void test_reference(void)
 {
     // Output message about test being performed
@@ -829,9 +824,7 @@ void test_reference(void)
 ** Purpose:	Cleanup temporary test files
 ** Return:	none
 ****************************************************************/
-#ifdef __cplusplus
 extern "C"
-#endif
 void cleanup_reference(void)
 {
     HDremove(FILE1.c_str());
diff --git a/c++/test/ttypes.cpp b/c++/test/ttypes.cpp
index 217b7b9..b77abf2 100644
--- a/c++/test/ttypes.cpp
+++ b/c++/test/ttypes.cpp
@@ -26,18 +26,13 @@
 #endif
 #include <string>
 
-#ifndef H5_NO_NAMESPACE
 #ifndef H5_NO_STD
     using std::cerr;
     using std::endl;
 #endif  // H5_NO_STD
-#endif
 
 #include "H5Cpp.h"      // C++ API header file
-
-#ifndef H5_NO_NAMESPACE
-    using namespace H5;
-#endif
+using namespace H5;
 
 #include "h5cpputil.h"  // C++ utilility header file
 
@@ -546,9 +541,7 @@ static void test_named ()
 **  test_types(): Main datatypes testing routine.
 **
 ****************************************************************/
-#ifdef __cplusplus
 extern "C"
-#endif
 void test_types()
 {
     // Output message about test being performed
@@ -578,9 +571,7 @@ void test_types()
  *
  *-------------------------------------------------------------------------
  */
-#ifdef __cplusplus
 extern "C"
-#endif
 void cleanup_types()
 {
     for (int i = 0; i < 3; i++)
diff --git a/c++/test/tvlstr.cpp b/c++/test/tvlstr.cpp
index 6ec7f25..a3e54c2 100644
--- a/c++/test/tvlstr.cpp
+++ b/c++/test/tvlstr.cpp
@@ -28,18 +28,13 @@
 #endif
 #include <string>
 
-#ifndef H5_NO_NAMESPACE
 #ifndef H5_NO_STD
     using std::cerr;
     using std::endl;
 #endif  // H5_NO_STD
-#endif
 
 #include "H5Cpp.h"      // C++ API header file
-
-#ifndef H5_NO_NAMESPACE
-    using namespace H5;
-#endif
+using namespace H5;
 
 #include "h5cpputil.h"  // C++ utilility header file
 
@@ -958,9 +953,7 @@ static void test_vl_rewrite()
  *
  *-------------------------------------------------------------------------
  */
-#ifdef __cplusplus
 extern "C"
-#endif
 void test_vlstrings()
 {
     // Output message about test being performed
@@ -1000,9 +993,7 @@ void test_vlstrings()
  *
  *-------------------------------------------------------------------------
  */
-#ifdef __cplusplus
 extern "C"
-#endif
 void cleanup_vlstrings()
 {
     HDremove(FILENAME.c_str());