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Initialize this driver by registering the driver with the library.

On success, returns the driver ID for the multi driver. On failure, returns a negative value.

hid_t H5FD_multi_init(void);

Sets the file access property list fapl_id to use the multi driver. The memb_map array maps memory usage types to other memory usage types and is the mechanism which allows the caller to specify how many files are created. The array contains h5fd_MEM_NTYPES entries which are either the value h5fd_MEM_DEFAULT or a memory usage type and the number of unique values determines the number of files which are opened. For each memory usage type which will be associated with a file the memb_fapl array should have a property list and the memb_name array should be a name generator (a printf-style format with a %s which will be replaced with the name passed to h5fd_open, usually from h5f_create or h5f_open).

If relax is set then opening an existing file for read-only access will not fail if some file members are missing. This allows a file to be accessed in a limited sense if just the meta data is available.

Default values for each of the optional arguments are:

memb_map

The default member map has the value h5fd_MEM_DEFAULT for each element.

memb_fapl

The value h5p_DEFAULT for each element.

memb_name

The string "%s-X.h5" where "X" is one of the letters "s" (h5fd_MEM_SUPER), "b" (h5fd_MEM_BTREE), "r" (h5fd_MEM_DRAW), "g" (h5fd_MEM_GHEAP), "l" (h5fd_MEM_LHEAP), "o" (h5fd_MEM_OHDR).

memb_addr

The value hADDR_UNDEF for each element.

Example: To set up a multi file access property list which partitions data into meta and raw files each being 1/2 of the address space one would say (TODO: translate to Haskell):

H5FD_mem_t mt, memb_map[H5FD_MEM_NTYPES];
hid_t memb_fapl[H5FD_MEM_NTYPES];
const char *memb[H5FD_MEM_NTYPES];
haddr_t memb_addr[H5FD_MEM_NTYPES];

// The mapping...
for (mt=0; mt<H5FD_MEM_NTYPES; mt++) {
    memb_map[mt] = H5FD_MEM_SUPER;
}
memb_map[H5FD_MEM_DRAW] = H5FD_MEM_DRAW;

// Member information
memb_fapl[H5FD_MEM_SUPER] = H5P_DEFAULT;
memb_name[H5FD_MEM_SUPER] = "%s.meta";
memb_addr[H5FD_MEM_SUPER] = 0;

memb_fapl[H5FD_MEM_DRAW] = H5P_DEFAULT;
memb_name[H5FD_MEM_DRAW] = "%s.raw";
memb_addr[H5FD_MEM_DRAW] = HADDR_MAX/2;

hid_t fapl = H5Pcreate(H5P_FILE_ACCESS);
H5Pset_fapl_multi(fapl, memb_map, memb_fapl,
                  memb_name, memb_addr, TRUE);

Returns non-negative on success, negative on failure.

herr_t H5Pset_fapl_multi(hid_t fapl_id, const H5FD_mem_t *memb_map,
       const hid_t *memb_fapl, const char * const *memb_name,
       const haddr_t *memb_addr, hbool_t relax);

Returns information about the multi file access property list though the function arguments which are the same as for h5p_set_fapl_multi above.

Returns non-negative on success, negative on failure.

herr_t H5Pget_fapl_multi(hid_t fapl_id, H5FD_mem_t *memb_map/*out*/,
       hid_t *memb_fapl/*out*/, char **memb_name/*out*/,
       haddr_t *memb_addr/*out*/, hbool_t *relax/*out*/);

Compatability function. Makes the multi driver act like the old split driver which stored meta data in one file and raw data in another file.

If the raw or meta extension string contains a "%s", it will be substituted by the filename given for h5f_open or h5f_create. If no %s is found, one is inserted at the beginning.

Returns non-negative on success, negative on failure.

herr_t H5Pset_fapl_split(hid_t fapl, const char *meta_ext,
       hid_t meta_plist_id, const char *raw_ext,
       hid_t raw_plist_id);