text: Provided by: libcanna1g-dev_3.7p3-14_amd64
  NAME
  RkXfer - change the current candidate
  SYNOPSIS
  #include <canna/RK.h> int RkXfer(cxnum, knum) int cxnum; int knum;
  DESCRIPTION
  RkXfer sets the candidate with a specified candidate number knum as the current candidate. The candidate number must be 0 or greater but less than the highest candidate number in the current clause. The current clause does not change when a candidate number outside this range is specified.
  RETURN VALUE
  If successful, this function moves the current candidate in the context and returns the candidate number after the move. It returns 0, without doing anything, if it has been run in a nonconversion mode context. RKXFER(3)