diary-anniversary

diary-anniversary is a compiled Lisp function in `diary-lib.el'.

(diary-anniversary MONTH DAY &optional YEAR MARK)

Anniversary diary entry.
Entry applies if date is the anniversary of MONTH, DAY, YEAR.
The order of the input parameters changes according to
`calendar-date-style' (e.g. to DAY MONTH YEAR in the European style).

The diary entry can contain `%d' or `%d%s'; the %d will be replaced
by the number of years since the MONTH, DAY, YEAR, and the %s will
be replaced by the ordinal ending of that number (that is, `st',
`nd', `rd' or `th', as appropriate). The anniversary of February 29
is considered to be March 1 in non-leap years.

An optional parameter MARK specifies a face or single-character
string to use when highlighting the day in the calendar.