Time and Date - clock

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Time and Date - clock
Example

Time and Date - clock

The clock command provides access to the time and date functions in Tcl. Depending on the subcommands invoked, it can acquire the current time, or convert between different representations of time and date.

The clock command is a platform independent method of getting the display functionality of the unix date command, and provides access to the values returned by a unix gettime() call.

clock seconds

The clock seconds command returns the time in seconds since the epoch. The date of the epoch varies for different operating systems, thus this value is useful for comparison purposes, or as an input to the clock format command.

clock format clockValue -gmt boolean -format string

The format subcommand formats a clockvalue clock clicks into a human readable string.

The -gmt switch takes a boolean as the second argument. If the boolean is 1 or True, then the time will be formatted as Greenwich Mean Time, otherwise, it will be formatted as local time.

The -format option controls what format the return will be in. The contents of the string %* descriptors that can be used to describe the output.

These include:

  • %a . . . . Abbreviated weekday name (Mon, Tue, etc.)

  • %A . . . . Full weekday name (Monday, Tuesday, etc.)

  • %b . . . . Abbreviated month name (Jan, Feb, etc.)

  • %B . . . . Full month name (January, February, etc.)

  • %d. . . . . Day of month

  • %j . . . . . Julian day of year

  • %m . . . . Month number (01-12)

  • %y. . . . . Year in century

  • %Y . . . . Year with 4 digits

  • %H . . . . Hour (00-23)

  • %I . . . . . Hour (00-12)

  • %M . . . . Minutes (00-59)

  • %S . . . . . Seconds(00-59)

  • %p . . . . . PM or AM

  • %D . . . . Date as %m/%d/%y

  • %r. . . . . Time as %I:%M:%S %p

  • %R . . . . Time as %I:%M

  • %T . . . . Time as %I:%M:%S

  • %Z . . . . Time Zone Name

clock scan dateString

The scan subcommand converts a human readable string to a system clock value, as would be returned by clock seconds

The dateString

time

A time of day in one of the formats shown below. Meridian may be AM, or PM, or a capitalization variant. If it is not specified, then the hour (hh) is interpreted as a 24 hour clock. Zone may be a three letter description of a time zone, EST, PDT, etc.

  • hh:mm:ss ?meridian? ?zone?

  • hhmm ?meridian? ?zone?

date

A date in one of the formats shown below.

  • mm/dd/yy

  • mm/dd

  • monthname dd, yy

  • monthname dd

  • dd monthname yy

  • dd monthname

  • day, dd monthname yy