The FitsChan constructor function, AST_FITSCHAN, is straightforward to use:
INCLUDE 'AST_PAR' INTEGER FITSCHAN, STATUS STATUS = 0 ... FITSCHAN = AST_FITSCHAN( AST_NULL, AST_NULL, 'Encoding=NATIVE', STATUS )
Here, we have omitted any source or sink functions by supplying the
AST_NULL routine for the first two arguments (remember to include the
AST_PAR include file which contains the required EXTERNAL statement
for this routine).
We have also initialised the FitsChan's Encoding attribute to
NATIVE. This indicates that we will be using the native encoding
() to store and retrieve Objects. If this
was left unspecified, the default would depend on the FitsChan's
contents. An attempt is made to use whatever encoding appears to have
been used previously. For an empty FitsChan, the default is NATIVE,
but it does no harm to be sure.
AST A Library for Handling World Coordinate Systems in Astronomy