diff --git a/.gitattributes b/.gitattributes
index 2f79ef6..be10b7a 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -375,6 +375,7 @@ src/C/H5Fed_retrieve.c -text
 src/C/H5Fed_store.c -text
 src/C/H5Fed_tags.c -text
 src/C/H5Part.c -text
+src/C/H5_attachments.c -text
 src/C/H5_attribs.c -text
 src/C/Makefile.am -text
 src/C/generate-h5b-readwrite.py -text
@@ -393,7 +394,7 @@ src/Fortran/TestUnderscore.f -text
 src/Fortran/TestUnderscoreC.c -text
 src/Makefile.am -text
 src/h5core/Makefile.am -text
-src/h5core/h5_attachments.c -text
+src/h5core/h5_attach.c -text
 src/h5core/h5_attribs.c -text
 src/h5core/h5_attribs_private.h -text
 src/h5core/h5_core_private.h -text
@@ -478,9 +479,11 @@ src/include/H5Fed_retrieve.h -text
 src/include/H5Fed_store.h -text
 src/include/H5Fed_tags.h -text
 src/include/H5Part.h -text
+src/include/H5_attachments.h -text
 src/include/H5_attribs.h -text
 src/include/H5hut.h -text
 src/include/grephdr -text
+src/include/h5core/h5_attach.h -text
 src/include/h5core/h5_attribs.h -text
 src/include/h5core/h5_core.h -text
 src/include/h5core/h5_errno.h -text
diff --git a/src/C/H5.c b/src/C/H5.c
index 6fee39c..b29d862 100644
--- a/src/C/H5.c
+++ b/src/C/H5.c
@@ -320,8 +320,7 @@ H5ReportErrorhandler (
 	const char* fmt,
 	va_list ap
 	) {
-	H5_API_ENTER (h5_err_t);
-	H5_API_RETURN (h5_report_errorhandler (fmt, ap));
+	return h5_report_errorhandler (fmt, ap);
 }
 
 h5_err_t
@@ -329,8 +328,7 @@ H5AbortErrorhandler (
 	const char* fmt,
 	va_list ap
 	) {
-	H5_API_ENTER (h5_err_t);
-	H5_API_RETURN (h5_abort_errorhandler (fmt, ap));
+	return h5_abort_errorhandler (fmt, ap);
 }
 
 /*!
@@ -342,10 +340,9 @@ H5AbortErrorhandler (
 */
 h5_err_t
 H5GetErrno (
-	h5_file_t* const f
+	void
 	) {
-	H5_API_ENTER (h5_err_t);
-	H5_API_RETURN (h5_get_errno ());
+	return h5_get_errno ();
 }
 
 
diff --git a/src/C/H5Fed.c b/src/C/H5Fed.c
index db9d53b..5fa1918 100644
--- a/src/C/H5Fed.c
+++ b/src/C/H5Fed.c
@@ -47,6 +47,7 @@ H5FedLinkMeshToStep (
 	h5_file_t* const f,
 	const h5_id_t mesh_id
 	) {
+	UNUSED_ARGUMENT (f);
 	UNUSED_ARGUMENT (mesh_id);
 	H5_API_ENTER (h5_err_t);
 	H5_API_RETURN (h5_error_not_implemented ());
diff --git a/src/C/H5_attachments.c b/src/C/H5_attachments.c
new file mode 100644
index 0000000..4fd97ac
--- /dev/null
+++ b/src/C/H5_attachments.c
@@ -0,0 +1,157 @@
+#include "h5core/h5_core.h"
+#include "H5hut.h"
+
+h5_ssize_t
+H5GetNumAttachments (
+	h5_file_t* const f	/*!< [in] Handle to open file */
+	) {
+	H5_API_ENTER (h5_ssize_t);
+	H5_API_RETURN (h5_get_num_attachments (f));
+}
+
+h5_err_t
+H5GetAttachmentInfoByIdx (
+	h5_file_t* const f,
+	const h5_size_t idx,		// IN
+	char* const name,		// OUT
+	h5_size_t len_name,		// IN
+	h5_int64_t* const type,		// OUT
+	h5_size_t* const npoints	// OUT
+	) {
+	H5_API_ENTER5 (h5_err_t, "idx=%llu, name=0x%p, len_name=%llu, type=0x%p, npoints=0x%p",
+		       idx, name, len_name, type, npoints);
+	H5_API_RETURN (h5_get_attachment_info_by_idx (
+			       f, idx, name, len_name, type, npoints));
+}
+
+h5_err_t
+H5GetAttachmentInfoByName (
+	h5_file_t* const f,
+	char* const name,		// OUT
+	h5_int64_t* const type,		// OUT
+	h5_size_t* const npoints	// OUT
+	) {
+	H5_API_ENTER3 (h5_err_t, "name=\"%s\", type=0x%p, npoints=0x%p",
+		       name, type, npoints);
+	H5_API_RETURN (h5_get_attachment_info_by_name (
+			       f, name, type, npoints));
+}
+
+h5_err_t
+H5WriteAttachmentBitstream (
+	h5_file_t* const f,		/*!< [in] Handle to open file */
+	const char* name,		/*!< [in] Name of attribute to create */
+	const void* const content,	/*!< [in] Value of attribute */ 
+	const h5_size_t size
+	) {
+	H5_API_ENTER3 (h5_err_t, "name=\"%s\", content=0x%p, size=%llu",
+		       name, content, (unsigned long long)size);
+	H5_API_RETURN (h5_write_attachment (f, name, H5T_NATIVE_CHAR, content, size));
+}
+
+h5_err_t
+H5WriteAttachmentFloat32 (
+	h5_file_t* const f,		/*!< [in] Handle to open file */
+	const char* name,		/*!< [in] Name of attribute to create */
+	const void* const content,	/*!< [in] Value of attribute */ 
+	const h5_size_t size
+	) {
+	H5_API_ENTER3 (h5_err_t, "name=\"%s\", content=0x%p, size=%llu",
+		       name, content, (unsigned long long)size);
+	H5_API_RETURN (h5_write_attachment (f, name, H5T_NATIVE_FLOAT, content, size));
+}
+
+h5_err_t
+H5WriteAttachmentFloat64 (
+	h5_file_t* const f,		/*!< [in] Handle to open file */
+	const char* name,		/*!< [in] Name of attribute to create */
+	const void* const content,	/*!< [in] Value of attribute */ 
+	const h5_size_t size
+	) {
+	H5_API_ENTER3 (h5_err_t, "name=\"%s\", content=0x%p, size=%llu",
+		       name, content, (unsigned long long)size);
+	H5_API_RETURN (h5_write_attachment (f, name, H5T_NATIVE_DOUBLE, content, size));
+}
+
+h5_err_t
+H5WriteAttachmentInt32 (
+	h5_file_t* const f,		/*!< [in] Handle to open file */
+	const char* name,		/*!< [in] Name of attribute to create */
+	const void* const content,	/*!< [in] Value of attribute */ 
+	const h5_size_t size
+	) {
+	H5_API_ENTER3 (h5_err_t, "name=\"%s\", content=0x%p, size=%llu",
+		       name, content, (unsigned long long)size);
+	H5_API_RETURN (h5_write_attachment (f, name, H5T_NATIVE_INT32, content, size));
+}
+
+h5_err_t
+H5WriteAttachmentInt64 (
+	h5_file_t* const f,		/*!< [in] Handle to open file */
+	const char* name,		/*!< [in] Name of attribute to create */
+	const void* const content,	/*!< [in] Value of attribute */ 
+	const h5_size_t size
+	) {
+	H5_API_ENTER3 (h5_err_t, "name=\"%s\", content=0x%p, size=%llu",
+		       name, content, (unsigned long long)size);
+	H5_API_RETURN (h5_write_attachment (f, name, H5T_NATIVE_INT64, content, size));
+}
+
+h5_err_t
+H5ReadAttachmentBitstream (
+	h5_file_t* const f,	/*!< [in] Handle to open file */
+	const char* name,	/*!< [in] Name of attribute to create */
+	void* const content	/*!< [in] Value of attribute */ 
+	) {
+	H5_API_ENTER2 (h5_err_t, "name=\"%s\", content=0x%p", name, content);
+	H5_API_RETURN (h5_read_attachment (f, name, H5T_NATIVE_CHAR, content));
+}
+
+h5_err_t
+H5ReadAttachmentFloat32 (
+	h5_file_t* const f,	/*!< [in] Handle to open file */
+	const char* name,	/*!< [in] Name of attribute to create */
+	void* const content	/*!< [in] Attachment */ 
+	) {
+	H5_API_ENTER2 (h5_err_t, "name=\"%s\", content=0x%p", name, content);
+	H5_API_RETURN (h5_read_attachment (f, name, H5T_NATIVE_FLOAT, content));
+}
+
+h5_err_t
+H5ReadAttachmentFloat64 (
+	h5_file_t* const f,	/*!< [in] Handle to open file */
+	const char* name,	/*!< [in] Name of attribute to create */
+	void* const content	/*!< [out] Attachment */ 
+	) {
+	H5_API_ENTER2 (h5_err_t, "name=\"%s\", content=0x%p", name, content);
+	H5_API_RETURN (h5_read_attachment (f, name, H5T_NATIVE_DOUBLE, content));
+}
+
+h5_err_t
+H5ReadAttachmentInt32 (
+	h5_file_t* const f,	/*!< [in] Handle to open file */
+	const char* name,	/*!< [in] Name of attribute to create */
+	void* const content	/*!< [out] Attachment */ 
+	) {
+	H5_API_ENTER2 (h5_err_t, "name=\"%s\", content=0x%p", name, content);
+	H5_API_RETURN (h5_read_attachment (f, name, H5T_NATIVE_INT32, content));
+}
+
+h5_err_t
+H5ReadAttachmentInt64 (
+	h5_file_t* const f,	/*!< [in] Handle to open file */
+	const char* name,	/*!< [in] Name of attribute to create */
+	void* const content	/*!< [out] Attachment */ 
+	) {
+	H5_API_ENTER2 (h5_err_t, "name=\"%s\", content=0x%p", name, content);
+	H5_API_RETURN (h5_read_attachment (f, name, H5T_NATIVE_INT64, content));
+}
+
+h5_err_t
+H5DeleteAttachment (
+	h5_file_t* const f,
+	const char* const name
+	) {
+	H5_API_ENTER1 (h5_err_t, "name=\"%s\"", name);
+	H5_API_RETURN (h5_delete_attachment (f, name));
+}
diff --git a/src/C/Makefile.am b/src/C/Makefile.am
index 26defe7..b907c24 100644
--- a/src/C/Makefile.am
+++ b/src/C/Makefile.am
@@ -16,6 +16,7 @@ include_HEADERS =				\
 	../include/H5hut.h			\
 	../include/H5.h				\
 	../include/H5_attribs.h			\
+	../include/H5_attachments.h		\
 	../include/H5Part.h                     \
 	../include/H5Block.h			\
 	../include/H5Block_readwrite.h		\
@@ -33,6 +34,7 @@ EXTRA_HEADERS =
 libH5hutC_a_SOURCES =				\
 	H5.c					\
 	H5_attribs.c				\
+	H5_attachments.c			\
 	H5Part.c                                \
 	H5Block.c				\
 	H5Block_readwrite.c			\
diff --git a/src/h5core/Makefile.am b/src/h5core/Makefile.am
index 9233d8b..eb94a30 100644
--- a/src/h5core/Makefile.am
+++ b/src/h5core/Makefile.am
@@ -6,6 +6,7 @@ LIBS = @LIBS@
 INCLUDES = -I../include @INCLUDES@
 
 EXTRA_HEADERS =					\
+	../include/h5core/h5_attach.h		\
 	../include/h5core/h5_attribs.h		\
 	../include/h5core/h5_core.h		\
 	../include/h5core/h5_errno.h		\
@@ -74,6 +75,7 @@ EXTRA_LIBRARIES = libH5hut.a
 
 # Listing of sources
 libH5hut_a_SOURCES =				\
+	h5_attach.c				\
 	h5_attribs.c				\
 	h5_errorhandling.c			\
 	h5_fcmp.c				\
diff --git a/src/h5core/h5_attachments.c b/src/h5core/h5_attach.c
similarity index 59%
rename from src/h5core/h5_attachments.c
rename to src/h5core/h5_attach.c
index b8f2d21..92f2cea 100644
--- a/src/h5core/h5_attachments.c
+++ b/src/h5core/h5_attach.c
@@ -1,5 +1,6 @@
 #include "h5core/h5_core.h"
 #include "h5_core_private.h"
+#include <string.h>
 
 static hid_t
 open_space_all (
@@ -12,27 +13,28 @@ open_space_all (
 }
 
 h5_err_t
-h5_add_attachment (
+h5_write_attachment (
 	h5_file_t* const f,
 	const char* const name,
-	h5_int64_t* const type,
+	const hid_t type,
 	const char* const content,
 	const h5_size_t size
 	) {
-	H5_CORE_API_ENTER2 (h5_ssize_t,
-			    "name=\"%s\, type=%d, content=0x%p",
-			    name, type, content);
+	H5_CORE_API_ENTER4 (h5_ssize_t,
+			    "name=\"%s\", type=%ld, content=0x%p, size=%llu",
+			    name, (long)type, content, (unsigned long long)size);
 	// write only on proc 0
 	if (f->myproc != 0) {
 		H5_CORE_API_LEAVE (H5_SUCCESS);
 	}
+	hid_t group_id;
 	TRY (group_id = h5priv_open_group (f, f->file, H5_ATTACHMENT));
+	h5_err_t exists;
         TRY (exists = hdf5_link_exists (group_id, name));
 	if (exists > 0) {
 		// warn user on overwrite
 		h5_warn ("Dataset %s/%s already exists",
 			 hdf5_get_objname(group_id), name);
-
 	}
 	h5_dsinfo_t dsinfo;
 	strncpy (dsinfo.name, name, sizeof (dsinfo.name) - 1);
@@ -57,13 +59,13 @@ static inline hid_t
 open_attachments (
 	h5_file_t* const f
 	) {
-	h5_err_t exists;
-        TRY (exists = hdf5_link_exists(f->file, H5_ATTACHMENT));
+	h5_err_t exists = hdf5_link_exists (f->file, H5_ATTACHMENT);
 	if (exists > 0) {
 		return hdf5_open_group (f->file, H5_ATTACHMENT);
-	} else {
+	} else if (exists == 0) {
 		return h5_warn ("No attachment group in file");
 	}
+	return exists;
 }
 
 h5_ssize_t
@@ -85,54 +87,96 @@ h5_get_num_attachments (
 h5_err_t
 h5_get_attachment_info_by_idx (
 	h5_file_t* const f,
-	const size_t idx,		// IN
+	const h5_size_t idx,		// IN
 	char* const name,		// OUT
-	size_t l_name,			// IN
+	h5_size_t len_name,		// IN
 	h5_int64_t* const type,		// OUT
 	h5_size_t* const npoints	// OUT
 	) {
 	H5_CORE_API_ENTER0 (h5_err_t);
-        TRY (group_id = open_attachments (f));
-	if (group_id < 0) {
+	hid_t loc_id;
+        TRY (loc_id = open_attachments (f));
+	if (loc_id < 0) { // no attachment group in file
 		H5_CORE_API_LEAVE (0);
 	}
-	TRY (hdf5_get_dataset_info_by_idx (group_id, idx, name, l_name, type, npoints));
-	TRY (hdf5_close_group (group_id));
-	H5_CORE_API_RETURN (num);
+	TRY (hdf5_get_name_of_dataset_by_idx (
+		     loc_id,
+		     idx,
+		     name, len_name));
+
+	if (npoints) {
+		// get number of elements, do not change value on error
+		h5_ssize_t np;
+		TRY (np = hdf5_get_npoints_of_dataset_by_name (loc_id, name));
+		*npoints = np;
+	}
+	if (type) {
+		// get normalized data type, do not change value on error
+		h5_int64_t t;
+		TRY (t = h5_get_dataset_type (loc_id, name));
+		*type = t;
+	}
+	TRY (hdf5_close_group (loc_id));
+	H5_CORE_API_RETURN (H5_SUCCESS);
 }
 
 h5_err_t
 h5_get_attachment_info_by_name (
 	h5_file_t* const f,
-	const char* const name,	// IN
-	h5_int64_t* const type,	// OUT
-	h5_size_t* const nelem	// OUT
+	const char* const name,		// IN
+	h5_int64_t* const type,		// OUT
+	h5_size_t* const npoints	// OUT
+	) {
+	H5_CORE_API_ENTER3 (h5_err_t,
+			    "name=\"%s\", type=0x%p, npoints=0x%p",
+			    name, type, npoints);
+
+	hid_t loc_id;
+        TRY (loc_id = open_attachments (f));
+	if (loc_id < 0) {
+		H5_CORE_API_LEAVE (H5_NOK);
+	}
+	if (npoints) {
+		h5_ssize_t np;
+		TRY (np = hdf5_get_npoints_of_dataset_by_name (loc_id, name));
+		*npoints = np;
+	}
+
+	if (type) {
+		h5_int64_t t;
+		TRY (t = h5_get_dataset_type (loc_id, name));
+		*type = t;
+	}
+	TRY (hdf5_close_group (loc_id));
+	H5_CORE_API_RETURN (H5_SUCCESS);
+}
+
+h5_err_t
+h5_read_attachment (
+	h5_file_t* const f,
+	const char* const name,
+	const hid_t type,
+	void* const content
 	) {
 	H5_CORE_API_ENTER0 (h5_err_t);
 	hid_t group_id;
         TRY (group_id = open_attachments (f));
-	if (group_id < 0) {
-		H5_CORE_API_LEAVE (H5_NOK);
-	}
-	TRY (hdf5_get_dataset_info_by_name (group_id, idx, name, type, npoints));
+	h5_dsinfo_t dsinfo;
+	strncpy (dsinfo.name, name, sizeof (dsinfo.name) - 1);
+	dsinfo.type_id = type;
+	TRY (h5priv_read_dataset_by_name (
+		f,
+		group_id,
+		&dsinfo,
+		open_space_all,
+		open_space_all,
+		content));
 	TRY (hdf5_close_group (group_id));
 	H5_CORE_API_RETURN (H5_SUCCESS);
 }
 
 h5_err_t
-h5_get_attachment (
-	h5_file_t* const f,
-	const char* const name,
-	const hid_t type,
-	void* const content,
-	) {
-	H5_CORE_API_ENTER0 (h5_err_t);
-	H5_CORE_API_RETURN (H5_SUCCESS);
-}
-
-
-h5_err_t
-h5_remove_attachment (
+h5_delete_attachment (
 	h5_file_t* const f,
 	const char* const name
 	) {
diff --git a/src/h5core/h5_core_private.h b/src/h5core/h5_core_private.h
index d5367d4..dab74e9 100644
--- a/src/h5core/h5_core_private.h
+++ b/src/h5core/h5_core_private.h
@@ -2,12 +2,15 @@
 #define __H5_CORE_PRIVATE_H
 
 #define H5_CORE_API_ENTER(type)		__FUNC_ENTER(type)
+#define H5_CORE_API_ENTER0(type)	__FUNC_ENTER(type)
 #define H5_CORE_API_ENTER1(type, fmt, a1)	\
 	__FUNC_ENTER1(type, fmt, a1, H5_DEBUG_CORE_API)
 #define H5_CORE_API_ENTER2(type, fmt, a1, a2)		\
 	__FUNC_ENTER2(type, fmt, a1, a2, H5_DEBUG_CORE_API)
 #define H5_CORE_API_ENTER3(type, fmt, a1, a2, a3)		\
 	__FUNC_ENTER3(type, fmt, a1, a2, a3, H5_DEBUG_CORE_API)
+#define H5_CORE_API_ENTER4(type, fmt, a1, a2, a3, a4)		\
+	__FUNC_ENTER4(type, fmt, a1, a2, a3, a4, H5_DEBUG_CORE_API)
 #define H5_CORE_API_LEAVE(value)	__FUNC_LEAVE(value)
 #define H5_CORE_API_RETURN(value)	__FUNC_RETURN(value, H5_DEBUG_CORE_API)
 
diff --git a/src/h5core/h5_hdf5.c b/src/h5core/h5_hdf5.c
index b2a136b..c9bdd86 100644
--- a/src/h5core/h5_hdf5.c
+++ b/src/h5core/h5_hdf5.c
@@ -1598,62 +1598,6 @@ hdf5_get_name_of_dataset_by_idx (
 	HDF5_WRAPPER_RETURN (H5_SUCCESS);
 }
 
-h5_err_t
-hdf5_get_dataset_info_by_idx (
-	const hid_t loc_id,		/*!< [in]  Group */
-	const hsize_t idx,		/*!< [in]  Index of the dataset */
-	char* const name,		/*!< [out] Name of dataset */
-	const size_t len_name,		/*!< [in]  Size of buffer \c name */
-	h5_int64_t* const type,		/*!< [out] Type of data in dataset */
-	hsize_t* const npoints		/*!< [out] Number of elements. */
-	) {
-	HDF5_WRAPPER_ENTER5 (h5_err_t,
-			     "loc_id=%d (%s), idx=%llu, name=0x%p, len_name=%llu",
-			     loc_id, hdf5_get_objname (loc_id),
-			     idx, name, (unsigned long long)len_name);
-
-	TRY (hdf5_get_name_of_dataset_by_idx (loc_id, idx, name, len_name));
-
-	if (npoints) {
-		h5_ssize_t np;
-		TRY (np = hdf5_get_npoints_of_dataset_by_name (loc_id, name));
-		*npoints = np;
-	}
-
-	if (type) {
-		h5_int64_t t;
-		TRY (t = h5_get_dataset_type (loc_id, name));
-		*type = t;
-	}
-	H5_CORE_API_RETURN (H5_SUCCESS);
-}
-
-h5_err_t
-hdf5_get_dataset_info_by_name (
-	const hid_t loc_id,		/*!< [in]  Group */
-	const hsize_t idx,		/*!< [in]  Index of the dataset */
-	const char* name,		/*!< [in] Name of dataset */
-	h5_int64_t* const type,		/*!< [out] Type of data in dataset */
-	hsize_t* const npoints		/*!< [out] Number of elements. */
-	) {
-	HDF5_WRAPPER_ENTER4 (h5_err_t,
-			     "loc_id=%d (%s), idx=%llu, name=\"%s\"",
-			     loc_id, hdf5_get_objname (loc_id),
-			     idx, name);
-	if (npoints) {
-		h5_ssize_t np;
-		TRY (np = hdf5_get_npoints_of_dataset_by_name (loc_id, name));
-		*npoints = np;
-	}
-
-	if (type) {
-		h5_int64_t t;
-		TRY (t = h5_get_dataset_type (loc_id, name));
-		*type = t;
-	}
-	H5_CORE_API_RETURN (H5_SUCCESS);
-}
-
 /****** I d e n t i f i e r **************************************************/
 
 const char *
diff --git a/src/h5core/h5_hdf5_private.h b/src/h5core/h5_hdf5_private.h
index cb66e2f..b2e263b 100644
--- a/src/h5core/h5_hdf5_private.h
+++ b/src/h5core/h5_hdf5_private.h
@@ -377,13 +377,4 @@ hdf5_delete_link (
 	hid_t lapl_id
 	);
 
-/*** other ***/
-h5_err_t
-hdf5_get_dataset_info_by_name (
-	const hid_t loc_id,
-	const hsize_t idx,
-	const char* name,
-	h5_int64_t* const type,
-	hsize_t* const npoints
-	);
 #endif
diff --git a/src/h5core/h5u_model.c b/src/h5core/h5u_model.c
index cd0ee79..4d4e4c1 100644
--- a/src/h5core/h5u_model.c
+++ b/src/h5core/h5u_model.c
@@ -408,24 +408,39 @@ h5u_get_num_datasets (
 
 /*!
   Get information about dataset in current index given by its index
- */
+*/
 h5_err_t
 h5u_get_dataset_info (
-	h5_file_t* const f,		/*!< [in]  Handle to open file */
-	const h5_id_t idx,		/*!< [in]  Index of the dataset */
-	char* const dset_name,		/*!< [out] Name of dataset */
-	const h5_size_t len_dset_name,	/*!< [in]  Size of buffer \c dset_name */
-	h5_int64_t* const type,		/*!< [out] Type of data in dataset */
-	h5_size_t* const npoints	/*!< [out] Number of elements. */
+	h5_file_t *const f,	/*!< [in] Handle to open file */
+	const h5_id_t idx,	/*!< [in] Index of the dataset */
+	char *dataset_name,	/*!< [out] Name of dataset */
+	const h5_size_t len_dataset_name,
+				/*!< [in] Size of buffer \c dataset_name */
+ 	h5_int64_t *type,	/*!< [out] Type of data in dataset */
+	h5_size_t *nelem	/*!< [out] Number of elements. */
 	) {
 	H5_CORE_API_ENTER (h5_err_t);
-	H5_CORE_API_RETURN (
-		hdf5_get_dataset_info_by_idx (
-			f->step_gid,
-			idx,
-			dset_name, len_dset_name,
-			type, npoints));
-}
+	TRY (hdf5_get_name_of_dataset_by_idx (
+		     f->step_gid,
+		     idx,
+		     dataset_name, len_dataset_name) );
+
+	if ( nelem ) {
+		h5_ssize_t nelem_;
+		TRY (nelem_ = hdf5_get_npoints_of_dataset_by_name (
+			     f->step_gid,
+			     dataset_name) );
+		if ( nelem_ < 0 ) return nelem_;
+		*nelem = nelem_;
+	}
+
+	if ( type ) {
+		*type = h5_get_dataset_type (f->step_gid, dataset_name);
+		if ( *type < 0 ) return *type;
+	}
+
+	H5_CORE_API_RETURN (H5_SUCCESS);
+} 
 
 h5_err_t
 h5u_set_chunk (
diff --git a/src/include/H5.h b/src/include/H5.h
index 4db566a..ebc7f0a 100644
--- a/src/include/H5.h
+++ b/src/include/H5.h
@@ -119,7 +119,7 @@ H5AbortErrorhandler (
 
 h5_err_t
 H5GetErrno (
-	h5_file_t * const f
+	void
 	);
 
 #ifdef PARALLEL_IO
diff --git a/src/include/H5_attachments.h b/src/include/H5_attachments.h
new file mode 100644
index 0000000..9137203
--- /dev/null
+++ b/src/include/H5_attachments.h
@@ -0,0 +1,108 @@
+#ifndef __H5_ATTACHMENTS_H
+#define __H5_ATTACHMENTS_H
+
+h5_ssize_t
+H5GetNumAttachments (
+	h5_file_t* const f
+	);
+
+h5_err_t
+H5GetAttachmentInfoByIdx (
+	h5_file_t* const f,
+	const h5_size_t idx,
+	char* const name,
+	h5_size_t len_name,
+	h5_int64_t* const type,
+	h5_size_t* const npoints
+	);
+
+h5_err_t
+H5GetAttachmentInfoByName (
+	h5_file_t* const f,
+	char* const name,
+	h5_int64_t* const type,
+	h5_size_t* const npoints
+	);
+
+h5_err_t
+H5WriteAttachmentBitstream (
+	h5_file_t* const f,
+	const char* name,
+	const void* const content,
+	const h5_size_t size
+	);
+
+h5_err_t
+H5WriteAttachmentFloat32 (
+	h5_file_t* const f,
+	const char* name,
+	const void* const content,
+	const h5_size_t size
+	);
+
+h5_err_t
+H5WriteAttachmentFloat64 (
+	h5_file_t* const f,
+	const char* name,
+	const void* const content,
+	const h5_size_t size
+	);
+
+h5_err_t
+H5WriteAttachmentInt32 (
+	h5_file_t* const f,
+	const char* name,
+	const void* const content,
+	const h5_size_t size
+	);
+
+h5_err_t
+H5WriteAttachmentInt64 (
+	h5_file_t* const f,
+	const char* name,
+	const void* const content,
+	const h5_size_t size
+	);
+
+h5_err_t
+H5ReadAttachmentBitstream (
+	h5_file_t* const f,
+	const char* name,
+	void* const content
+	);
+
+h5_err_t
+H5ReadAttachmentFloat32 (
+	h5_file_t* const f,
+	const char* name,
+	void* const content
+	);
+
+h5_err_t
+H5ReadAttachmentFloat64 (
+	h5_file_t* const f,
+	const char* name,
+	void* const content
+	);
+
+h5_err_t
+H5ReadAttachmentInt32 (
+	h5_file_t* const f,
+	const char* name,
+	void* const content
+	);
+
+h5_err_t
+H5ReadAttachmentInt64 (
+	h5_file_t* const f,
+	const char* name,
+	void* const content
+	);
+
+h5_err_t
+H5DeleteAttachment (
+	h5_file_t* const f,
+	const char* const name
+	);
+
+#endif
diff --git a/src/include/H5hut.h b/src/include/H5hut.h
index 4c5c550..c4400b7 100644
--- a/src/include/H5hut.h
+++ b/src/include/H5hut.h
@@ -8,6 +8,7 @@ extern "C" {
 #include "h5core/h5_core.h"
 #include "H5.h"
 #include "H5_attribs.h"
+#include "H5_attachments.h"
 #include "H5Part.h"
 #include "H5Block.h"
 #include "H5Block_readwrite.h"
diff --git a/src/include/h5core/h5_attach.h b/src/include/h5core/h5_attach.h
new file mode 100644
index 0000000..025eef7
--- /dev/null
+++ b/src/include/h5core/h5_attach.h
@@ -0,0 +1,50 @@
+#ifndef __H5_ATTACH_H
+#define __H5_ATTACH_H
+
+h5_err_t
+h5_write_attachment (
+	h5_file_t* const f,
+	const char* const name,
+	const hid_t type,
+	const char* const content,
+	const h5_size_t size
+	);
+
+h5_ssize_t
+h5_get_num_attachments (
+	h5_file_t* const f
+	);
+
+h5_err_t
+h5_get_attachment_info_by_idx (
+	h5_file_t* const f,
+	const h5_size_t idx,		// IN
+	char* const name,		// OUT
+	h5_size_t len_name,		// IN
+	h5_int64_t* const type,		// OUT
+	h5_size_t* const npoints	// OUT
+	);
+
+h5_err_t
+h5_get_attachment_info_by_name (
+	h5_file_t* const f,
+	const char* const name,		// IN
+	h5_int64_t* const type,		// OUT
+	h5_size_t* const npoints	// OUT
+	);
+
+h5_err_t
+h5_read_attachment (
+	h5_file_t* const f,
+	const char* const name,
+	const hid_t type,
+	void* const content
+	);
+
+h5_err_t
+h5_delete_attachment (
+	h5_file_t* const f,
+	const char* const name
+	);
+
+#endif
diff --git a/src/include/h5core/h5_core.h b/src/include/h5core/h5_core.h
index 21623fb..8365ed6 100644
--- a/src/include/h5core/h5_core.h
+++ b/src/include/h5core/h5_core.h
@@ -14,13 +14,13 @@
 #define H5_DEBUG_ALL		(-1)
 
 extern char* h5_rfmts[];
-#define __FUNC_ENTER(type)		\
+#define __FUNC_ENTER(type)			\
 	h5_call_stack_push (__func__,e_##type); \
 	type ret_value = (type)H5_ERR;
 
-#define __FUNC_ARGS0(mask)		\
+#define __FUNC_ARGS0(mask)			\
 	if (h5_debug_level & mask ) {		\
-		h5_debug ("(void)");	\
+		h5_debug ("(void)");		\
 	}
 
 #define __FUNC_ARGS1(fmt, a1, mask)		\
@@ -69,7 +69,7 @@ extern char* h5_rfmts[];
 	__FUNC_ARGS4(fmt, a1, a2, a3, a4, mask);
 
 #define __FUNC_ENTER5(type, fmt, a1, a2, a3, a4, a5, mask)	\
-	__FUNC_ENTER(type);				\
+	__FUNC_ENTER(type);					\
 	__FUNC_ARGS5(fmt, a1, a2, a3, a4, a5, mask);
 
 #define __FUNC_LEAVE(expr) {			\
@@ -80,8 +80,8 @@ extern char* h5_rfmts[];
 #define __FUNC_RETURN(expr, mask)		\
 	ret_value = expr;			\
 	goto done;				\
-done:						\
-	if (h5_debug_level & mask ) {			\
+done:								\
+	if (h5_debug_level & mask ) {  				\
 		char fmt[256];					\
 		snprintf (fmt, sizeof(fmt), "return: %s",	\
 			  h5_rfmts[h5_call_stack_get_type()]);	\
@@ -109,6 +109,14 @@ done:						\
 	H5_API_ENTER(type);			\
 	__FUNC_ARGS3(fmt, a1,a2,a3, H5_DEBUG_API)
 
+#define H5_API_ENTER4(type, fmt, a1, a2, a3, a4)	\
+	H5_API_ENTER(type);				\
+	__FUNC_ARGS4(fmt, a1,a2,a3, a4, H5_DEBUG_API)
+
+#define H5_API_ENTER5(type, fmt, a1, a2, a3, a4, a5)	\
+	H5_API_ENTER(type);				\
+	__FUNC_ARGS5(fmt, a1,a2,a3, a4, a5, H5_DEBUG_API)
+
 #define H5_API_LEAVE(expr)		__FUNC_LEAVE(expr)
 #define H5_API_RETURN(expr)		__FUNC_RETURN(expr, H5_DEBUG_API);
 
@@ -135,6 +143,7 @@ done:						\
 #include "h5_types.h"
 #include "h5_errno.h"
 
+#include "h5_attach.h"
 #include "h5_attribs.h"
 #include "h5_hdf5.h"
 #include "h5_maps.h"
diff --git a/src/include/h5core/h5_hdf5.h b/src/include/h5core/h5_hdf5.h
index d11d9f0..4f59a89 100644
--- a/src/include/h5core/h5_hdf5.h
+++ b/src/include/h5core/h5_hdf5.h
@@ -33,16 +33,6 @@ hdf5_get_name_of_dataset_by_idx (
 	size_t len
 	);
 
-h5_err_t
-hdf5_get_dataset_info_by_idx (
-	const hid_t loc_id,
-	const hsize_t idx,
-	char* const name,
-	const size_t len_name,
-	h5_int64_t* const type,
-	hsize_t* const npoints
-	);
-
 const char *
 hdf5_get_objname (
 	hid_t id