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Extending HCL OneDB™Beyond standard relational database objects, HCL OneDB™ can be extended to handle specialized data types, access methods, routines, and other objects. HCL OneDB™ includes many built-in extensions that are fully integrated in the database server. HCL OneDB™ also provides DataBlade® modules, which are packages of extended database objects for a particular purpose and that are installed separately from the database server. Alternatively, you can create your own user-defined objects for HCL OneDB™.
Creating extensionsYou can create user-defined data types, routines, access methods, and other database objects to suit your needs. You can use application programming interfaces to write user-defined routines and applications that access data in HCL OneDB™ databases.
DataBlade® API Function ReferenceThe HCL OneDB™ DataBlade® API Function Reference describes the DataBlade® API functions and the subset of functions that the DataBlade® API supports.
Function descriptionsThis section gives comprehensive reference information about the functions that are valid within DataBlade® API modules. It lists the function descriptions in alphabetical order, with syntax, usage information, and return values for the functions.
The mi_file_seek8() functionThe mi_file_seek8() function sets the file seek position for the next read or write operation on an open file of length greater that 2 GB.

The mi_file_seek8() function

The mi_file_seek8() function sets the file seek position for the next read or write operation on an open file of length greater that 2 GB.

Syntax

mi_integer mi_file_seek8(fd, offset8, newpos8, whence)
   mi_integer fd;
   mi_int8  *offset8,
   mi_int8  *newpos8,
   mi_integer whence;

fd: The file descriptor for the operating-system file on which to set the seek position. The file descriptor is obtained by a previous call to the mi_file_open() function.
offset8: A pointer to the eight-byte integer (mi_int8) offset from the specified whence file seek position
newpos8: A pointer to the eight-byte integer (mi_int8) that identifies the new file seek position.
whence: This value determines how to interpret the offset value.


Valid in client LIBMI application?	Valid in user-defined routine?
Yes	Yes

Usage

The mi_file_seek8() function uses the whence and offset arguments to determine the new seek position of the file that fd identifies, as follows:

The whence argument identifies the position from which to start the seek operation.
Valid values include the following whence constants for both client and server files.

Whence constant
Starting seek position

SEEK_SET

Set position equal to offset bytes

SEEK_CUR

Set position to current location plus offset

SEEK_END

Set position to EOF plus offset
The offset argument identifies the offset, in bytes, from the starting seek position (which the whence argument specifies) at which to begin the seek.
This offset value can be negative for all values of whence. To obtain the current seek position for an open smart large object, use the mi_file_tell8() function.

Server only: In a C UDR, this function can move to a new seek position in a file that resides on either the server or client computer. You specify the location of the file when you open it with mi_file_open() function.

Return values

MI_OK: The function was successful and provides the seek position in the newpos8 variable.
MI_ERROR: The function was not successful.

The mi_file_seek8() function does not throw an MI_Exception event when it encounters a runtime error. Therefore, it does not cause callbacks to start.