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Name

date - write the date and time

Synopsis

/usr/bin/date [-u] [+format]
/usr/bin/date [-a [-]sss.fff]
/usr/bin/date [-u] [[mmdd]HHMM | mmddHHMM[cc]yy][.SS]

/usr/xpg4/bin/date [-u] [+format]
/usr/xpg4/bin/date [-a [-]sss.fff]
/usr/xpg4/bin/date [-u] [[mmdd]HHMM | mmddHHMM[cc]yy][.SS]

Availability

/usr/bin/date

SUNWcsu

/usr/xpg4/bin/date

SUNWxcu4

Description

The date utility writes the date and time to standard output or attempts to set the system date and time. By default, the current date and time will be written.

Specifications of native language translations of month and weekday names are supported. The month and weekday names used for a language are based on the locale specified by the environment variable LC_TIME ; see environ(5) .

The following is the default form for the "C" locale:

%a %b %e %T %Z %Y

for example,

Fri Dec 23 10:10:42 EST 1988

Options

The following options are supported:
-a [-]sss.fff
Slowly adjust the time by sss.fff seconds (fff represents fractions of a second). This adjustment can be positive or negative. The system’s clock will be sped up or slowed down until it has drifted by the number of seconds specified.
-u
Display (or set) the date in Greenwich Mean Time (GMT --universal time), bypassing the normal conversion to (or from) local time.

Operands

The following operands are supported:
+format
If the argument begins with +, the output of date is the result of passing format and the current time to strftime(). date uses the conversion specifications listed on the strftime(3C) manual page, with the conversion specification for %C determined by whether /usr/bin/date or /usr/xpg4/bin/date is used:
/usr/bin/date
Locale’s date and time representation. This is the default output for date.
/usr/xpg4/bin/date
Century (a year divided by 100 and truncated to an integer) as a decimal number [00-99].

The string is always terminated with a NEWLINE . An argument containing blanks must be quoted; see the EXAMPLES section.

mm
Month number
dd
Day number in the month
HH
Hour number (24 hour system)
MM
Minute number
SS
Second number
cc
Century minus one
yy
Last 2 digits of the year number
The month, day, year, and century may be omitted;
the current values are applied as defaults. For example:

date 10080045

sets the date to Oct 8, 12:45 a.m. The current year is the default because no year is supplied. The system operates in GMT . date takes care of the conversion to and from local standard and daylight time. Only the super-user may change the date. After successfully setting the date and time, date displays the new date according to the default format. The date command uses TZ to determine the correct time zone information; see environ(5) .

Examples

The command 


example% date ’+DATE: %m/%d/%y%nTIME: %H:%M:%S’

generates as output: 


DATE: 08/01/76
TIME: 14:45:05
The command 


example# date 1234.56

sets the current time to 12:34:56.

Environment

See environ(5) for descriptions of the following environment variables that affect the execution of date: LC_CTYPE , LC_TIME , LC_MESSAGES , and NLSPATH .
TZ
Determine the timezone in which the time and date are written, unless the -u option is specified. If the TZ variable is not set and the -u is not specified, the system default timezone is used.

Exit Status

The following exit values are returned:
  1. Successful completion.
    >0
    An error occurred.

    See Also

    strftime(3C) , environ(5)

    Diagnostics

    no permission
    You are not the super-user and you tried to change the date.
    bad conversion
    The date set is syntactically incorrect.

    Notes

    If you attempt to set the current date to one of the dates that the standard and alternate time zones change (for example, the date that daylight time is starting or ending), and you attempt to set the time to a time in the interval between the end of standard time and the beginning of the alternate time (or the end of the alternate time and the beginning of standard time), the results are unpredictable.

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