VFD SWMR: Normalization with develop (#1078)

Brings many changes from develop, particularly VOL changes for async

1 files changed, 38 insertions, 0 deletions

diff --git a/doxygen/dox/cookbook/Attributes.dox b/doxygen/dox/cookbook/Attributes.dox
new file mode 100644
index 0000000..68fd159
--- /dev/null
+++ b/doxygen/dox/cookbook/Attributes.dox
@@ -0,0 +1,38 @@
+/** \page Attributes
+
+\section Attributes
+
+\subsection CB_LargeAttributes Creating "Large" HDF5 Attributes
+
+\par Problem
+You would like to use HDF5 attributes the size of whose values
+exceeds a few dozen kilobytes
+
+\par Solution
+A file format change in the HDF5 1.8.x family of library releases made it
+possible to have attributes larger than about 64 KiB. Ensure that the lower
+library version bound for new HDF5 item creation is at least 1.8.x, and create
+larger attributes as usual.\n
+In the example below, we create an attribute whose value occupies 4 MiB.
+
+\note This feature is only supported in HDF5 1.8.x+
+
+\snippet{lineno} Attributes.c large_attribute
+
+\par Discussion
+Large attributes are supported only in HDF5 versions 1.8.x and higher.
+This has implications for the accessibility of your HDF5 files and
+is your call.\n
+Since there are no size limitations for large attributes, it might
+seem tempting to mistake them for dataset stand-ins. This is not the
+case, for at least two reasons:
+1. Attributes decorate HDF5 objects, have their own local namespace,
+   and can't be link targets.
+2. Attribute I/O treats the attribute value as atomic, i.e., there
+   is no support for partial I/O. A large attribute will always be
+   read or written in its entirety.
+
+\par See Also
+See \ref CB_MaintainCompat for HDF5 compatibility implications.
+
+ */
\ No newline at end of file