convertclock(1tcl)

convertclock -- convert date string to integer value

Synopsis

convertclock dateString [GMT|{}] [baseClock]

Description

Converts dateString to an integer clock value (see getclock). This command can parse and convert virtually any standard date and/or time string, which can include standard time zone mnemonics. If only a time is specified, the current date is assumed. If the string does not contain a time zone mnemonic, the local time zone is assumed, unless the GMT argument is specified, in which case the clock value is calculated assuming that the specified time is relative to Greenwich Mean Time. If baseClock is specified, it is taken as the current clock value. This is useful for determining the time on a specific day.

The character string consists of zero or more specifications of the following form:

time: A time of day, which is of the form hh[:mm[:ss]] [meridian] [zone] or hhmm [meridian] [zone]. If no meridian is specified, hh is interpreted on a 24-hour clock.
date: A specific month and day with optional year. The acceptable formats are mm/dd[/yy], yyyy/mm/dd, monthname dd[, yy], dd monthname [yy], and day, dd monthname yy. The default year is the current year. If the year is less than 100, then 1900 is added to it.
relative time: A specification relative to the current time. The format is number unit; acceptable units are year, fortnight, month, week, day, hour, minute (or min), and second (or sec). The unit can be specified as a singular or plural, as in ``3 weeks''. These modifiers may also be specified: tomorrow, yesterday, today, now, last, this, next, ago.

The actual date is calculated according to the following steps. First, any absolute date and/or time is processed and converted. Using that time as the base, day-of-week specifications are added. Next, relative specifications are used. If a date or day is specified, and no absolute or relative time is given, midnight is used. Finally, a correction is applied so that the correct hour of the day is produced after allowing for daylight savings time differences.

convertclock ignores case when parsing all words. The names of the months and days of the week can be abbreviated to their first three letters, with optional trailing period. Periods are ignored in any timezone or meridian values.

Examples

convertclock "14 Feb 92"
convertclock "Feb 14, 1992 12:20 PM PST"
convertclock "12:20 PM Feb 14, 1992"