1Usage: datediff [OPTION]... DATE/TIME [DATE/TIME]... 2 3Compute duration from DATE/TIME (the reference date/time) to the other 4DATE/TIMEs given and print the result as duration. 5If the other DATE/TIMEs are omitted read them from stdin. 6 7DATE/TIME can also be one of the following specials 8 - `now' interpreted as the current (UTC) time stamp 9 - `time' the time part of the current (UTC) time stamp 10 - `today' the current date (according to UTC) 11 - `tomo[rrow]' tomorrow's date (according to UTC) 12 - `y[ester]day' yesterday's date (according to UTC) 13 14Note: The output format of durations (specified via -f) takes all format 15specifiers into account, i.e. specifying %M and %S for example prints the 16duration in minutes and seconds, whereas specifying %S only prints the duration 17in seconds. 18 19See section `The refinement rule' in ddiff(1). 20 21 -h, --help Print help and exit 22 -V, --version Print version and exit 23 -q, --quiet Suppress message about date/time and duration 24 parser errors and fix-ups. 25 The default is to print a warning or the 26 fixed up value and return error code 2. 27 Also see -S|--skip-illegal to output an empty 28 line instead of leaving out the line altogether. 29 -S, --skip-illegal Output empty lines as placeholder for illegal 30 input, i.e. parser errors or date/times that 31 cannot be subtracted. 32 -f, --format=STRING Output format. This can either be a specifier 33 string (similar to strftime()'s FMT) or the name 34 of a calendar. 35 -i, --input-format=STRING... Input format, can be used multiple times. 36 Each date/time will be passed to the input 37 format parsers in the order they are given, if a 38 date/time can be read successfully with a given 39 input format specifier string, that value will 40 be used. 41 -b, --base=DT For underspecified input use DT as a fallback to 42 fill in missing fields. Also used for ambiguous 43 format specifiers to position their range on the 44 absolute time line. 45 Must be a date/time in ISO8601 format. 46 If omitted defaults to the current date/time. 47 -e, --backslash-escapes Enable interpretation of backslash escapes in the 48 output and input format specifier strings. 49 --from-locale=LOCALE Interpret dates on stdin or the command line as 50 coming from the locale LOCALE, this would only 51 affect month and weekday names as input formats 52 have to be specified explicitly. 53 --from-zone=ZONE Interpret dates on stdin or the command line as 54 coming from the time zone ZONE. 55