Glossary

ICS file

A text file in the iCalendar format with a .ics extension. Defined by RFC 5545.

RFC 5545

The Internet standard that defines the iCalendar format. Specifies the structure of .ics files, component types, properties, and recurrence rules.

VCALENDAR

The top-level wrapper component in an .ics file. Contains all other components.

VEVENT

A calendar event. Has a start time (DTSTART), optional end time (DTEND), and optional recurrence rules.

VTODO

A to-do item. Like a VEVENT but represents a task rather than a scheduled event. May have a due date instead of an end time.

VJOURNAL

A journal entry. Represents a note or record associated with a date.

VALARM

An alarm attached to a VEVENT or VTODO. Has a trigger time (absolute or relative to the parent component). Not included in default output — use -c VALARM to query alarms.

VTIMEZONE

A timezone definition embedded in a calendar file. Defines the UTC offset and daylight saving rules for a named timezone.

DTSTART

The start date or date-time of a component. For recurring components, this is the start of the first occurrence.

DTEND

The end date or date-time of a component. Exclusive — an event ending at 10:00 does not overlap a query starting at 10:00.

RRULE

A recurrence rule. Defines how a component repeats — daily, weekly, monthly, and so on. ics-query expands these into individual occurrences automatically.

EXDATE

A list of dates excluded from a recurrence series. Occurrences on these dates are skipped.

occurrence

A single instance of a component. A weekly recurring event has one occurrence per week. ics-query filters and returns occurrences, not the raw recurring rule.

recurrence

A component that repeats over time, defined by an RRULE. ics-query uses recurring-ical-events to expand recurrences into individual occurrences.

floating time

A date-time with no timezone. Interpreted as local time wherever it is read. Contrast with a timezone-aware date-time which has a fixed TZID.

X-WR-TIMEZONE

A non-standard calendar property used by some applications (e.g., Google Calendar exports) to specify a calendar-wide timezone. ics-query handles this automatically.