This slide illustrates the date/time formats used and returned by F$CVTIME(). Times can be returned in comparison format which is suitable for “IF” statements, absolute format which is suitable for /AFTER, /BEFORE and /SINCE qualifier values, or delta format which is suitable for use in other date expressions to arrive at another date based on the delta expression.
Note, however, that F$CVTIME() cannot calculate the delta between two date/time expressions.
