Informix DataBlade API Programmer's Manual DataBlade API Function Descriptions

The mi_file_seek() function seeks a specified location on an operating-system file.

mi_integer mi_file_seek(fd, offset, whence)

mi_integer fd;

mi_integer offset;

mi_integer whence;

fd	is a file descriptor for the operating-system file whose seek position you want to change. It is obtained by a previous call to mi_file_open().
offset	is a pointer to the integer offset from the starting seek position.
whence	determines how the offset is interpreted.

Valid in Client LIBMI Application?	Valid in User-Defined Routine?
Yes	Yes

The mi_file_seek() function uses the whence and offset arguments to determine the seek position, as follows:

• The whence argument identifies the position from which to start the seek operation.

Valid values include the following whence constants.

Whence Constant	Starting Seek Position
MI_LO_SEEK_SET	The start of the operating-system file
MI_LO_SEEK_CUR	The current seek position in the operating-system file
MI_LO_SEEK_END	The end of the operating-system file

• 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. The mi_file_tell() function returns the current seek position for an open smart large object.

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

See the descriptions of the following functions: mi_file_open(), mi_file_read(), mi_file_tell(), and mi_file_write().