gfs_pio_set_view_index3
Change file view to an individual fragment
Usage
#include <gfarm/gfarm.h>
char *gfs_pio_set_view_index (GFS_File gf, int fragment_number, int fragment_index, char *host, int flags);
Overview
gfs_pio_set_view_index() changes the process's view of the data in the file specified by gf to a file fragment with the index fragment_index.
When creating a new file, it is necessary to specify the total number of file fragments fragment_number. Every parallel process should specify the same fragment_number for the corresponding file. When the file exists, GFARM_FILE_DONTCARE can be specified. If fragment_number is different from the total fragment number of the existent file, it is erroneous.
host is used for explicitly specifying a filesystem node. If host is NULL, appropriate filesystem node is chosen.
Values of flag are constructed by a bitwise-inclusive-OR of the following list.
GFARM_FILE_SEQUENTIAL-
File will be accessed sequentially.
GFARM_FILE_REPLICATE-
File may be replicated to a local filesystem when accessing remotely. This flag cannot be specified with GFARM_FILE_NOT_REPLICATE.
GFARM_FILE_NOT_REPLICATE-
File may not be replicated to a local filesystem when accessing remotely. This flag cannot be specified with GFARM_FILE_REPLICATE.
By default, Gfarm files are accessed as a whole file in global file view where each fragment can be seamlessly accessed.
Return values
- NULL
-
The function terminated successfully.
GFARM_ERR_NO_MEMORY-
Insufficient memory was available.
GFARM_ERR_OPERATION_NOT_PERMITTED-
The file is not a regular fragmented file.
GFARM_ERR_FRAGMENT_NUMBER_DOES_NOT_MATCH-
The total number of file fragments is different from the existence one.
GFARM_ERR_INVALID_ARGUMENT-
Invalid arguments are specified, for instance, GFARM_FILE_DONTCARE is specified as the total number of fragments of a newly created file.
Others-
An error except the above occurred. The reason is shown by its pointed strings.
Releases
Unchanged in 2 releases since Debian 6.0 (Squeeze).