%N fitwrhdh %F $MIR/src/subs/fitsio.for
%D Write a string to a FITS file header.
%P rjs
%: fits
%B
      subroutine fitwrhdh(lu,key,value)

      integer lu
      character key*(*),value*(*)
  ---------------------------------------------------------------------
  Write a comment or history card.

  Input:
    lu         File descriptor.
    key        FITS keyword (usually HISTORY).
    value      The comment to write.
