Oracle Sun SPARC Enterprise M3000 Reference Manual page 443

-t time Specifies the start date and time of the display range for log data.
It is specified in one of the following formats:
yyyy-mm-dd,hh:mm
mm/dd/yy,hh:mm
Monddhh:mmyyyy
yyyy-mm-dd,hh:mm:ss
mm/dd/yy,hh:mm:ss
Monddhh:mm:ssyyyy
Even if the -r option is specified together with this option, the
specified -t and -T options are not reversed. The -t option
cannot be used for the monitoring message log.
The timestamp is specified in the 'year-month-day, hour:minute'
format.
The timestamp is specified in the 'month/day/year, hour:minute'
format.
The timestamp is specified in the 'month-name, day, hour:minute,
year' format.
The timestamp is specified in the 'year-month-day,
hour:minute:second' format.
The timestamp is specified in the 'month/day/year,
hour:minute:second' format.
The timestamp is specified in the 'month-name, day,
hour:minute:second, year' format.
showlogs(8)
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