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/* -*- c-file-style: "stroustrup" -*- */
#include "hdf5.h"
#include <stdio.h>
#include <stdlib.h>
#define H5P_DEFAULTx2 H5P_DEFAULT, H5P_DEFAULT
int
main(void)
{
int ret_val = EXIT_SUCCESS;
//! <!-- [create] -->
{
__label__ fail_file;
hid_t file, group;
char src_path[] = "/a/few/groups";
if ((file = H5Fcreate("o1.h5", H5F_ACC_TRUNC, H5P_DEFAULTx2)) == H5I_INVALID_HID) {
ret_val = EXIT_FAILURE;
goto fail_file;
}
// create a few groups
{
__label__ fail_group, fail_lcpl;
hid_t lcpl;
if ((lcpl = H5Pcreate(H5P_LINK_CREATE)) == H5I_INVALID_HID) {
ret_val = EXIT_FAILURE;
goto fail_lcpl;
}
if (H5Pset_create_intermediate_group(lcpl, 1) < 0) {
ret_val = EXIT_FAILURE;
goto fail_group;
}
if ((group = H5Gcreate(file, src_path, lcpl, H5P_DEFAULTx2)) == H5I_INVALID_HID) {
ret_val = EXIT_FAILURE;
goto fail_group;
}
H5Gclose(group);
fail_group:
H5Pclose(lcpl);
fail_lcpl:;
}
// create a copy
if (H5Ocopy(file, ".", file, "copy of", H5P_DEFAULTx2) < 0) {
ret_val = EXIT_FAILURE;
}
H5Fclose(file);
fail_file:;
}
//! <!-- [create] -->
//! <!-- [read] -->
{
__label__ fail_info, fail_file;
hid_t file;
char path[] = "/a/few/groups";
H5O_info2_t info;
if ((file = H5Fopen("o1.h5", H5F_ACC_RDONLY, H5P_DEFAULT)) == H5I_INVALID_HID) {
ret_val = EXIT_FAILURE;
goto fail_file;
}
// retrieve information about the object
if (H5Oget_info_by_name(file, path, &info, H5O_INFO_BASIC | H5O_INFO_NUM_ATTRS, H5P_DEFAULT) < 0) {
ret_val = EXIT_FAILURE;
goto fail_info;
}
// determine the object type
switch (info.type) {
case H5O_TYPE_GROUP:
printf("HDF5 group\n");
break;
case H5O_TYPE_DATASET:
printf("HDF5 dataset\n");
break;
case H5O_TYPE_NAMED_DATATYPE:
printf("HDF5 datatype\n");
break;
default:
printf("UFO?\n");
break;
}
// print basic information
printf("Reference count: %u\n", info.rc);
printf("Attribute count: %lld\n", info.num_attrs);
fail_info:
H5Fclose(file);
fail_file:;
}
//! <!-- [read] -->
//! <!-- [update] -->
{
__label__ fail_obj, fail_incr, fail_file;
hid_t file, obj;
char path[] = "/a/few/groups";
H5O_info2_t info;
if ((file = H5Fopen("o1.h5", H5F_ACC_RDWR, H5P_DEFAULT)) == H5I_INVALID_HID) {
ret_val = EXIT_FAILURE;
goto fail_file;
}
// open an object by path name
if ((obj = H5Oopen(file, path, H5P_DEFAULT)) == H5I_INVALID_HID) {
ret_val = EXIT_FAILURE;
goto fail_obj;
}
// bump its reference count (by 1)
if (H5Oincr_refcount(obj) < 0) {
ret_val = EXIT_FAILURE;
goto fail_incr;
}
// confirm the new reference count
if (H5Oget_info(obj, &info, H5O_INFO_BASIC) < 0) {
ret_val = EXIT_FAILURE;
goto fail_incr;
}
printf("Reference count: %u\n", info.rc);
fail_incr:
H5Oclose(obj);
fail_obj:
H5Fclose(file);
fail_file:;
}
//! <!-- [update] -->
//! <!-- [delete] -->
{
__label__ fail_obj, fail_delete, fail_file;
hid_t file, obj;
char path[] = "/a/few/groups";
H5O_info2_t info;
if ((file = H5Fopen("o1.h5", H5F_ACC_RDWR, H5P_DEFAULT)) == H5I_INVALID_HID) {
ret_val = EXIT_FAILURE;
goto fail_file;
}
// open an object by path name
if ((obj = H5Oopen(file, path, H5P_DEFAULT)) == H5I_INVALID_HID) {
ret_val = EXIT_FAILURE;
goto fail_obj;
}
// render it inaccessible from the root group by deleting the one and
// only link to it; this drops the reference count by 1
if (H5Ldelete(file, path, H5P_DEFAULT) < 0) {
ret_val = EXIT_FAILURE;
goto fail_delete;
}
// confirm the new reference count
if (H5Oget_info(obj, &info, H5O_INFO_BASIC) < 0) {
ret_val = EXIT_FAILURE;
goto fail_delete;
}
printf("Reference count: %u\n", info.rc);
// if we close the file at this point, we'd be creating a tombstone,
// an object that cannot be reached and that cannot be reclaimed by the
// freespace manager; decrement the reference count to zero to prevent that
if (H5Idec_ref(obj) < 0) {
ret_val = EXIT_FAILURE;
goto fail_delete;
}
else
// attempting to close the object would be like a double H5Oclose and fail
goto fail_obj;
fail_delete:
H5Oclose(obj);
fail_obj:
H5Fclose(file);
fail_file:;
}
//! <!-- [delete] -->
return ret_val;
}
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