seek
Sets the current position in the #GIOChannel, similar to the standard library function fseek().
Return
%G_IO_ERROR_NONE if the operation was successful.
Parameters
offset
an offset, in bytes, which is added to the position specified by @type
type
the position in the file, which can be %G_SEEK_CUR (the current position), %G_SEEK_SET (the start of the file), or %G_SEEK_END (the end of the file)