- Created by Mike McGreevy, last modified by Barbara Jones on May 07, 2018
H5O_MCDT_SEARCH_CB_T
Provides the mechanism by which a user application may set an action for H5O_COPY to take after checking all suggested paths for a matching committed datatype but before starting the global search of the destination file
Signature:
typedef H5O_mcdt_search_ret_t ( *H5O_mcdt_search_cb_t )( void *op_data )
Parameters:
void *op_data | IN/OUT: Pointer to user-defined input data. This is a pass-through of the data that was passed to H5P_SET_MCDT_SEARCH_CB. |
Description:
H5O_MCDT_SEARCH_CB_T is the callback function that H5O_COPY will invoke if the callback is set and when the merge committed datatype feature is enabled in the object copy property list (see H5P_SET_COPY_OBJECT).
After searching the list of suggested committed datatype paths, H5O_COPY will invoke this callback before searching all committed datatypes in the destination file. This allows a user application to add a customized step to the search process. The callback function is set with H5P_SET_MCDT_SEARCH_CB and the search process is described in H5P_ADD_MERGE_COMMITTED_DTYPE_PATH.
Valid return values from this callback function are as follows (defined in the enumerated datatype H5O_mcdt_search_ret_t in H5Opublic.h):
H5O_MCDT_SEARCH_ERROR | Aborts H5O_COPY |
H5O_MCDT_SEARCH_CONT | Continues the global search of all committed datatypes in the destination file |
H5O_MCDT_SEARCH_STOP | Stops the search, but continues copying |
If the callback’s return value is H5O_MCDT_SEARCH_ERROR, H5O_COPY will abort and the destination file may be left in an inconsistent or corrupted state.
Returns:
Returns one of the H5O_MCDT_SEARCH_* values described above.
Failure Modes:
H5O_MCDT_SEARCH_CB_T failure modes are dependent on the implementation of the callback function.
Example:
This example defines a callback function in the object copy property list to discontinue the global search if a matching committed datatype cannot be found among the suggested paths.
/* The user-defined callback function */
static H5O_mcdt_search_ret_t
mcdt_search_cb(void *_udata)
{
H5O_mcdt_search_ret_t action = *((H5O_mcdt_search_ret_t *)_udata);
return(action);
}
int main(void) {
hid_t ocpypl_id = H5Pcreate(H5P_OBJECT_COPY);
/* Enable the merging committed datatype feature. */
H5Pset_copy_object(ocpypl_id, H5O_COPY_MERGE_COMMITTED_DTYPE_FLAG);
/* Add the path to search for a matching committed datatype. */
H5Padd_merge_committed_dtype_path(ocpypl_id, "/group/committed_dtypeA");
/*
* Set the callback function to discontinue the global search
* if H5Ocopy cannot find a matching committed datatype from the
* above suggested path.
*/
action = H5O_MCDT_SEARCH_STOP;
H5Pset_mcdt_search_cb(ocpypl_id, mcdt_search_cb, &action);
/* Do the copy. */
H5Ocopy(...ocpypl_id...);
...
...
}
History:
| Release | Change |
| 1.8.9 | C function type introduced in this release. |
--- Last Modified: May 07, 2018 | 03:53 PM