This function shows the spec underlying iCal files.
ic_spec(mode = "view",
spec_url = "https://tools.ietf.org/rfc/rfc5545.txt")
character string specifying whether to look at the spec (mode = "view"
, the default)
or read it in (mode = "read"
)
the location of the latest version of the spec, from tools.ietf.org/rfc/rfc5545.txt by default