G.2.3.1 Difference value %[format]? special texts

The use of the other difference values as listed here is to calculate distance values between two dates. In case these special texts are directly lead by a ‘-’ character, e.g. ‘-%d’, Gcal switches the sign of the computed value.

You may depreciate the special meaning of the ‘-’ character —in case this character itself is needed— by placing a ‘\’ (backslash) character before it, e.g. ‘\-’. If you need the ‘\-’ characters themselves, you have to protect the ‘\’ (backslash) character by another ‘\’ (backslash) character, e.g. ‘\\-’.

The following other difference values %[format]? special texts are respected:

%d

Specifies the current respectively queried day relative to the actual system date (≡today), e.g.:

The resource file line ‘0 %d days gone’ will be expanded to
→ ‘-10 days gone’, in case you call Gcal with the -c10- option and no command.

%w

Specifies the current respectively queried week relative to the actual system date (≡today). Started weeks are counted as complete weeks.

%m

Specifies the current respectively queried month relative to the actual system date (≡today). Started months are counted as complete months.

%y

Specifies the current respectively queried year relative to the actual system date (≡today). Started years are counted as complete years. This special text must always be trailed by a whitespace character which is removed in output!

An example:

Supposing, the actual system date is the 4th September 1999. To calculate, how many days, weeks, months and years are between the actual system date and the birthday of a person, who is born on 21st September 1962, Gcal can be called as follows:

$ gcal -f/dev/null -Ux -u -#'19620921 %y %m %w %d~' 1962
-|
-| -37 -444 -1928 -13497
-|
$ gcal -f/dev/null -Ux -u -#'19620921 \\-%y \-%m %w -%d~' 1962
-|
-| \--37 --444 -1928 13497
-|
$ gcal -f/dev/null -Ux -u -#'00000904 %y %m %w %d~' %19620921 1999
-|
-| 37 444 1928 13497
-|
$ gcal -f/dev/null -Ux -u -#'00000904 %y %B19620921' %19620921 1962
-|
-| 37 36

Please do not confound the relative year number %[format]y special text with the age value %B special text (see Age value %[format]B[date] special text). The %y special text counts started years as complete years, while the %B special text does not.