Interface to slalib routines and TSTAMP, the time stamp structure <DATE>
typedef struct Tstamp { int year; /* year (1995, for example) */ int month; /* month (1 to 12) */ int day; /* day (1 to 31) */ int hour; /* hour (0 to 23) */ int minute; /* minute (0 to 59) */ double second; /* second (0 to 59.99999) */ TSTAMP;