Displaying diary messages in standard summary line format (usually something like ‘From Joe: Subject’) is pretty useless. Most of the time, you're the one who wrote the message, and you mostly want to see the event's date.
gnus-diary provides two supplemental user formats to be used in
summary line formats.
D corresponds to a formatted time string
for the next occurrence of the event (e.g., “Sat, Sep 22 01, 12:00”),
d corresponds to an approximate remaining time until the
next occurrence of the event (e.g., “in 6 months, 1 week”).
For example, here's how Joe's birthday is displayed in my
nndiary+diary:birthdays summary buffer (note that the message is
expirable, but will never be deleted, as it specifies a periodic event):
E Sat, Sep 22 01, 12:00: Joe's birthday (in 6 months, 1 week)
In order to get something like the above, you would normally add the following line to your diary groups'parameters:
(gnus-summary-line-format "%U%R%z %uD: %(%s%) (%ud)\n")
gnus-diary does it automatically (see Diary Group Parameters). You can however customize the provided summary line format
with the following user options:
Defines the summary line format used for diary groups (see Summary Buffer Lines).
gnus-diaryuses it to automatically update the diary groups'parameters.
Defines the format to display dates in diary summary buffers. This is used by the
Duser format. See the docstring for details.
Defines the format function to use for displaying delays (remaining times) in diary summary buffers. This is used by the
duser format. There are currently built-in functions for English and French; you can also define your own. See the docstring for details.