Delete the current FITS card in a FitsChan astDelFits
After deletion, the following card becomes the current card.
This function returns without action if the FitsChan is initially positioned at the "
end-of-file"
(i.e. if the Card attribute exceeds the number of cards in the
FitsChan).
If there are no subsequent cards in the FitsChan, then the Card attribute is left
pointing at the "
end-of-file"
after deletion (i.e. is set to one more than the number
of cards in the FitsChan).