Last modified: 23 August 2012
Name: H5Pregister2
Signature:
  herr_t `H5Pregister2`( hid_t `class`, const char * `name`, size_t `size`, void * `default`, H5P_prp_create_func_t `create`, H5P_prp_set_func_t `set`, H5P_prp_get_func_t `get`, H5P_prp_delete_func_t `delete`, H5P_prp_copy_func_t `copy`, H5P_prp_compare_func_t `compare`, H5P_prp_close_func_t `close` )

Purpose:
  Registers a permanent property with a property list class.

Description:
  `H5Pregister2` registers a new property with a property list class. The property will exist in all property list objects of `class` created after this routine finishes. The name of the property must not already exist, or this routine will fail. The default property value must be provided and all new property lists created with this property will have the property value set to the default value. Any of the callback routines may be set to NULL if they are not needed.

  Zero-sized properties are allowed and do not store any data in the property list. These may be used as flags to indicate the presence or absence of a particular piece of information. The default pointer for a zero-sized property may be set to NULL. The property `create` and `close` callbacks are called for zero-sized properties, but the `set` and `get` callbacks are never called.

  The `create` routine is called when a new property list with this property is being created. The `H5P_prp_create_func_t` callback function is defined as follows:

  typedef herr_t (*`H5P_prp_create_func_t`)( const char *`name`, size_t `size`, void *`initial_value`);
  The parameters to this callback function are defined as follows:

  const char *`name` | IN: The name of the property being modified
  size_t `size` | IN: The size of the property in bytes
  void *`initial_value` | IN/OUT: The default value for the property being created, which will be passed to `H5Pregister2`

  The `create` routine may modify the value to be set and those changes will be stored as the initial value of the property. If the `create` routine returns a negative value, the new property value is not copied into the property and the create routine returns an error value.

  The `set` routine is called before a new value is copied into the property. The `H5P_prp_set_func_t` callback function is defined as follows:

  typedef herr_t (*H5P_prp_set_func_t)( hid_t `prop_id`, const char *`name`, size_t `size`, void *`new_value`);
  The parameters to this callback function are defined as follows:

  hid_t `prop_id` | IN: The identifier of the property list being modified
  const char *`name` | IN: The name of the property being modified
  size_t `size` | IN: The size of the property in bytes
  void **`new_value` | IN/OUT: Pointer to new value pointer for the property being modified

  The `set` routine may modify the value pointer to be set and those changes will be used when setting the property's value. If the `set` routine returns a negative value, the new property value is not copied into the property and the `set` routine returns an error value. The `set` routine will not be called for the initial value, only the `create` routine will be called.

  Note: The `set` callback function may be useful to range check the value being set for the property or may perform some transformation or translation of the value set. The `get` callback would then reverse the transformation or translation. A single `get` or `set` callback could handle multiple properties by performing different actions based on the property name or other properties in the property list.

  The `get` routine is called when a value is retrieved from a property value. The `H5P_prp_get_func_t` callback function is defined as follows:

  typedef herr_t (*`H5P_prp_get_func_t`)( hid_t `prop_id`, const char *`name`, size_t `size`, void *`value`);
  The parameters to the callback function are defined as follows:

  hid_t `prop_id` | IN: The identifier of the property list being queried
  const char * `name` | IN: The name of the property being queried
  size_t `size` | IN: The size of the property in bytes
  void * `value` | IN/OUT: The value of the property being returned

  The `get` routine may modify the value to be returned from the query and those changes will be returned to the calling routine. If the `set` routine returns a negative value, the query routine returns an error value.

  The `delete` routine is called when a property is being deleted from a property list. The `H5P_prp_delete_func_t` callback function is defined as follows:

  typedef herr_t (*`H5P_prp_delete_func_t`)( hid_t `prop_id`, const char *`name`, size_t `size`, void *`value`);
  The parameters to the callback function are defined as follows:

  hid_t `prop_id` | IN: The identifier of the property list the property is being deleted from
  const char * `name` | IN: The name of the property in the list
  size_t `size` | IN: The size of the property in bytes
  void * `value` | IN: The value for the property being deleted

  The `delete` routine may modify the value passed in, but the value is not used by the library when the `delete` routine returns. If the `delete` routine returns a negative value, the property list delete routine returns an error value but the property is still deleted.

  The `copy` routine is called when a new property list with this property is being created through a copy operation. The `H5P_prp_copy_func_t` callback function is defined as follows:

  typedef herr_t (*`H5P_prp_copy_func_t`)( const char *`name`, size_t `size`, void *`value`);
  The parameters to the callback function are defined as follows:

  const char *`name` | IN: The name of the property being copied
  size_t `size` | IN: The size of the property in bytes
  void *`value` | IN/OUT: The value for the property being copied

  The `copy` routine may modify the value to be set and those changes will be stored as the new value of the property. If the `copy` routine returns a negative value, the new property value is not copied into the property and the copy routine returns an error value.

  The `compare` routine is called when a property list with this property is compared to another property list with the same property. The `H5P_prp_compare_func_t` callback function is defined as follows:

  typedef int (*`H5P_prp_compare_func_t`)( const void *`value1`, const void *`value2`, size_t `size`);
  The parameters to the callback function are defined as follows:

  const void *`value1` | IN: The value of the first property to compare
  const void *`value2` | IN: The value of the second property to compare
  size_t `size` | IN: The size of the property in bytes

  The `compare` routine may not modify the values. The `compare` routine should return a positive value if `value1` is greater than `value2`, a negative value if `value2` is greater than `value1` and zero if `value1` and `value2` are equal.

  The `close` routine is called when a property list with this property is being closed. The `H5P_prp_close_func_t` callback function is defined as follows:

  typedef herr_t (*`H5P_prp_close_func_t`)( hid_t `prop_id`, const char *`name`, size_t `size`, void *`value`);
  The parameters to the callback function are defined as follows:

  hid_t `prop_id` | IN: The identifier of the property list being closed
  const char *`name` | IN: The name of the property in the list
  size_t `size` | IN: The size of the property in bytes
  void *`value` | IN: The value for the property being closed

  The `close` routine may modify the value passed in, but the value is not used by the library when the `close` routine returns. If the `close` routine returns a negative value, the property list close routine returns an error value but the property list is still closed.

Programming Note for C++ Developers Using C Functions:

  If a C routine that takes a function pointer as an argument is called from within C++ code, the C routine should be returned from normally.

  Examples of this kind of routine include callbacks such as `H5Pset_elink_cb` and `H5Pset_type_conv_cb` and functions such as `H5Tconvert` and `H5Ewalk2`.

  Exiting the routine in its normal fashion allows the HDF5 C Library to clean up its work properly. In other words, if the C++ application jumps out of the routine back to the C++ “catch” statement, the library is not given the opportunity to close any temporary data structures that were set up when the routine was called. The C++ application should save some state as the routine is started so that any problem that occurs might be diagnosed.

Parameters:

hid_t `class` | IN: Property list class to register permanent property within
const char * `name` | IN: Name of property to register
size_t `size` | IN: Size of property in bytes
void * `default` | IN: Default value for property in newly created property lists
H5P_prp_create_func_t `create` | IN: Callback routine called when a property list is being created and the property value will be initialized
H5P_prp_set_func_t `set` | IN: Callback routine called before a new value is copied into the property's value
H5P_prp_get_func_t `get` | IN: Callback routine called when a property value is retrieved from the property
H5P_prp_delete_func_t `delete` | IN: Callback routine called when a property is deleted from a property list
H5P_prp_copy_func_t `copy` | IN: Callback routine called when a property is copied from a property list
H5P_prp_compare_func_t `compare` | IN: Callback routine called when a property is compared with another property list
H5P_prp_close_func_t `close` | IN: Callback routine called when a property list is being closed and the property value will be disposed of

Returns:
  Success: a non-negative value
  Failure: a negative value

Fortran90 Interface:
  None.

History:

  Release | C
  1.8.0 | Function introduced in this release.