localtime Tcl Command

NAME

localtime - Obtain the current time and/or date

SYNOPSIS

::dmh::localtime ?format?

DESCRIPTION

This command is used to obtain the current system time. Unless UTC (Universal Coordinated Time) is indicated, the result is for the local timezone. UTC time was formerly known as GMT (Greenwich Mean Time). The environmental variable TZ should be set to establish or override the local timezone, and the use of Daylight Saving Time. This variable is usually configured by the system administrator when the operating system is installed.

The value of the argument format controls the output format of the result. If no format code is given or if the code is out of range, the default format is used. The following format codes are supported. These format choices are also available for the mktime command.

default
YYYY MM DD HH MM SS DayOfWeek DayOfYear With this format, single digit numbers are padded with a space so that the first 6 fields are always at the same offsets in the string. DayOfWeek ranges 0 to 6 with 0 being Sunday. DayofYear ranges from 0 to 365 with 0 being January 1. In general, single digit numbers are padded with leading zeroes on all of the other formats. The leading 0's may need to be removed if the text is used in integer expressions since the usual Tcl input routines use leading zeroes to indicate octal values.
0
The C language asctime() result string for the local time; for example Sun May 28 19:03:43 1995. This result format does not depend on the current locale (configured Country and language).
1
Same as the above except but the value is for UTC.
2
The POSIX count of seconds since 1970 eg., 801705320
3
HHMMSS
4
HH:MM:SS
5
YYYYMMDD
6
YYYY MM DD
7
MM DD YY
8
DD-Mon-YYYY HH:MM:SS
9
YYYY-MM-DD HH:MM:SS in the local timezone. Formats 9, 10, 15 and 16 are especially useful for sorting when ordinary string comparison is used.
10
YYYY-MM-DD HH:MM:SS for UTC
11
UTC_seconds microseconds This format is available if your system supports the gettimeofday() C function. The localtime command guarantees that a unique, monotonically increasing result is returned everytime format 11, format 15, or format 16 is obtained, but this result usually does not have the full millisecond accuracy. For example, on Win32 platforms, the microseconds argument is only accurate to the nearest millisecond. The mktime command can be used to convert this format into any of the other formats.
12
date and time formatted for the current locale using the strftime() function, format "%c".
13
date formatted for the current locale using the strftime() function, format "%x".
14
time formatted for the current locale using the strftime() function, format "%X".
15
YYYY-MM-DD HH:MM:SS.uuuuuu in the local timezone. If you use this value for a database key, you may have problems with Daylight Saving Time in the fall, when the clock is shifted back an hour. As with format 11, this format is available only on platforms that support gettimeofday().
16
YYYY-MM-DD HH:MM:SS.uuuuuu for UTC. This value is free of problems with Daylight Saving Time changes. As with format 11, this format is available only on platforms that support gettimeofday().
17
YYYY-MM-DD HH:MM:SS.mmm in the local timezone. This format is available only on platforms that support gettimeofday().
18
YYYY-MM-DD HH:MM:SS.mmm for UTC. This value is free of problems with Daylight Saving Time changes. This format is available only on platforms that support gettimeofday().
reset
This command argument causes the discarding of cached system time values that are used to return unique values for the 11, 15, and 16 format choices. The subcommand needs to be called if the computer system clock is updated to an earlier time while the application is running.

AUTHOR

Ed Hume, Hume Integration Software

SEE ALSO

mktime   dmh_ntp_install

KEYWORDS

time, calender, date, mktime