The localtime() function returns an array identical to that of the structure returned by the C function call.
The optional timestamp parameter is an integer Unix timestamp that defaults to the current local time if a timestamp is not given. In other words, it defaults to the value of time().
If set to FALSE or not supplied than the array is returned as a regular, numerically indexed array. If the argument is set to TRUE then localtime() is an associative array containing all the different elements of the structure returned by the C function call to localtime. The names of the different keys of the associative array are as follows:
"tm_sec" - seconds
"tm_min" - minutes
"tm_hour" - hour
"tm_mday" - day of the month
Months are from 0 (Jan) to 11 (Dec) and days of the week are from 0 (Sun) to 6 (Sat).
"tm_mon" - month of the year, starting with 0 for January
"tm_year" - Years since 1900
"tm_wday" - Day of the week
"tm_yday" - Day of the year
"tm_isdst" - Is daylight savings time in effect
Every call to a date/time function will generate a E_NOTICE if the time zone is not valid, and/or a E_STRICT message if using the system settings or the TZ environment variable. See also date_default_timezone_set()