- Created by Barbara Jones, last modified on Aug 12, 2019
H5P_INSERT2
Registers a temporary property with a property list
Procedure:
H5P_INSERT2 ( plid, name, size, value, set, get, delete, copy, compare, close )
Signature:
herr_t H5Pinsert2(
hid_t plid,
const char *name,
size_t size,
void *value,
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
)
NONE
Parameters:
hid_t plid | IN: Property list identifier to create temporary property within |
const char * name | IN: Name of property to create |
size_t size | IN: Size of property in bytes |
void * value | IN: Initial value for the property |
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 an existing 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 |
Description:
H5P_INSERT2 creates a new property in a property list. The property will exist only in this property list and copies made from it.
The initial property value must be provided in value
and the property value will be set accordingly.
The name of the property must not already exist in this list, or this routine will fail.
The set
and get
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. The default value of a zero-size property may be set to NULL. They may be used to indicate the presence or absence of a particular piece of information.
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 the 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: 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 be called for the initial value.
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 above callback function are:
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: 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 preserved. If the get
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 above callback function are:
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 above callback function are:
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 )( 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 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, 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.
Note: There is no create
callback routine for temporary property list objects; the initial value is assumed to have any necessary setup already performed on it.
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 H5P_SET_ELINK_CB and H5P_SET_TYPE_CONV_CB and functions such as H5T_CONVERT and H5E_WALK2.
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.
Returns:
Success: a non-negative value Failure: a negative value
Example:
Coming Soon!
History:
Release | Change |
---|---|
1.8.0 | Function introduced in this release. |
--- Last Modified: August 12, 2019 | 12:00 PM