HP-UX更改系统时间

y666y

HP-UX更改系统时间 使用命令date命令 如果使用date -u 修改时间，需要当前时间减去8小时

本机为当地北京时间08:44:30，需要系统时间设置如下：
$ date                              ----表示EAT东区时间                                                                        
2013年1月8日 星期二, 08:44:30
$ date -u                           ----表示UTC（UTC-8=EAT）时间，翻译过来是：协调世界时(Universal Time Coordinated)



date(1)                                                            date(1)

NAME
     date - display or set the date and time

SYNOPSIS
     date [-u]

     date [-u] +format

     date [-u] [mmddhhmm[[cc]yy]]

     date [-a [-]sss[.fff]]

DESCRIPTION
     The date command displays or sets the current HP-UX system clock date
     and time. Since the HP-UX system operates in Coordinated Universal
     Time (UTC), date automatically converts to and from local standard or
     daylight/summer time, based on your TZ environment variable. See
     Environment Variables in EXTERNAL INFLUENCES below.

   Options
     date recognizes the following option:

          -u  Input and output values in Coordinated Universal Time (UTC),
               functionally equivalent to Greenwich Mean Time (GMT),
               instead of in local time.

          -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.

   Formats
     The date command has two forms for displaying the date and time and
     one form for setting them.

          date [-u]

                  Display the current date and time. The output is the
                  same as for the %c formatting directive for all languages
                  except the C default language. See Formatting Directives
                  and EXAMPLES below.

          date [-u] +format

                  Display the current date and time according to formatting
                  directives specified in format, which is a string of zero
                  or more formatting directives and ordinary characters.
                  If it contains blanks, enclose it in apostrophes or
                  quotation marks.

Hewlett-Packard Company           - 1 -  HP-UX Release 11i: November 2000

date(1)                                                            date(1)

                  See Formatting Directives below.

                  All ordinary characters are copied unchanged into the
                  output string.

                  The output string is always terminated with a newline
                  character.

                  If + is specified and format is omitted, only a newline
                  is output.

          date [-u] [mmddhhmm[[cc]yy]]

                  Set the HP-UX system clock to the date and time
                  specified. You require the superuser privilege.

                  If you include the -u option, the specified date and time
                  is assumed to be in Coordinated Universal Time (UTC).

                  The numeric argument is interpreted left to right in
                  two-digit pairs as follows:

                       mm  Month number [01-12].
                       dd  Day number in the month [01-31].
                       hh  Hour number (24-hour system) [00-23].
                       mm  Minute number [00-59].
                       cc  Century minus one [19-20].
                       yy  Last two digits of the year number [70-99, 00-
                            37 (1970-1999, 2000-2037)]. If omitted, the
                            current year is used.

                  If you attempt to set the date backwards, date generates
                  the warning,

                       do you really want to run time backwards?[yes/no]

                  Type yes or the equivalent for your locale to set the
                  clock backwards; anything else to cancel the command.

                  When date is used to set the date, a pair of date change
                  records is written to the file /var/adm/wtmp.

                  (XPG4 only.) No warning is generated if date is set
                  backwards.

Hewlett-Packard Company           - 2 -  HP-UX Release 11i: November 2000

date(1)                                                            date(1)

   Formatting Directives
     The following formatting directives, shown without the optional field
     width and precision specification, are replaced by the indicated
     characters. If a directive is not one of the following, the result is
     undefined.

     The output for digits, characters, and words depends on the
     language/locale settings. See Environment Variables in EXTERNAL
     INFLUENCES below.

     The examples assume that the date command was executed on Wednesday,
     January 12, 1994 at 7:45:58 p.m. Pacific Standard Time, using the C
     default language.

          %a  Abbreviated weekday name. For example, Wed.

          %A  Full weekday name. For example, Wednesday.

          %b  Abbreviated month name. For example, Jan.

          %B  Full month name. For example, January.

          %c  Current date and time representation. For example, Wed Jan
               12 19:45:58 1994.

          %C  Century (the year divided by 100 and truncated to an
               integer) as a two-digit decimal number [00-99]. For
               example, 19.

          %d  Day of the month as a two-digit decimal number [01-31]. For
               example, 12.

          %e  Day of the month as a two-character decimal number with
               leading space fill [" 1"-"31" ]. For example, 12.

          %E  Combined Emperor/Era name and year.

          %H  Hour (24-hour clock) as a two-digit decimal number [00-23].
               For example, 19.

          %I  Hour (12-hour clock) as a two-digit decimal number [01-12].
               For example, 07.

          %j  Day of the year as a three-digit decimal number [001-366].
               For example, 012.

          %m  Month as a decimal two-digit number [01-12]. For example,
               01.

          %M  Minute as a decimal two-digit number [00-59]. For example,
               45.

Hewlett-Packard Company           - 3 -  HP-UX Release 11i: November 2000

date(1)                                                            date(1)

          %n  Newline character.

          %N  Emperor/Era name.

          %o  Emperor/Era year.

          %p  Equivalent of either AM or PM. For example, PM.

          %R  Time as %H:%M

          %S  Second as a two-digit decimal number (allows for possible
               leap seconds) [00-61]. For example, 58.

          %t  Tab character.

          %u  Weekday as a one-digit decimal number [1-7 (Monday-Sunday)].
               For example, 3.

          %U  Week number of the year (Sunday as the first day of the
               week) as a two-digit decimal number [00-53]. All days that
               precede the first Sunday in the year are considered to be in
               week 00. For example, 02.

          %V  Week number of the year (Monday as the first day of the
               week) as a two-digit decimal number [01-53]. If the week
               containing January 1 has four or more days in the new year
               (January 1 is Thursday or sooner), it is designated as week
               01; otherwise, (January 1 is Friday or later), it is
               designated as the last week of the previous year, and the
               next week is week 01. For example, 02.

          %w  Weekday as a one-digit decimal number [0-6 (Sunday-
               Saturday)]. For example, 3.

          %W  Week number of the year (Monday as the first day of the
               week) as a two-digit decimal number [00-53]. All days that
               precede the first Monday in the year are considered to be in
               week 00. For example, 02.

          %x  Current date representation. For example, 01/12/94.

          %X  Current time representation. For example, 19:45:58.

          %y  Year without century as a two-digit decimal number [00-99].
               For example, 93.

          %Y  Year with century as a four-digit decimal number [1970-
               2037]. For example, 1994.

          %Z  Time zone name (or no characters if time zone cannot be
               determined). For example, PST.

Hewlett-Packard Company           - 4 -  HP-UX Release 11i: November 2000

date(1)                                                            date(1)

          %%  The % character.

   Obsolescent Directives
     The following directives are provided for backward compatibility. It
     is recommended that the preceding directives be used instead.

          %D  Date in usual U.S. format. For example, 01/12/94. Use %x
               or %m/%d/%y instead.

          %F  Full month name. For example, January. Use %B instead.

          %h  Abbreviated month name. For example, Jan. Use %b instead.

          %r  Time in 12-hour U.S. format. For example, 07:45:58 PM. Use
               "%I:%M:%S %p" instead.

          %T  Time in 24-hour U.S. format. For example, 19:45:58. Use %X
               or %H:%M:%S instead.

          %z  Time zone name (or no characters if time zone cannot be
               determined). For example, PST. Use %Z instead.

   Modified Formatting Directives
     Some Formatting Directives can be modified by the E and O modifier
     characters to indicate a different format or specification for the
     language specified in the LC_TIME environment variable.

     If the corresponding keyword (era, era_year, era_d_fmt, and alt_digit)
     is not specified or not supported, the unmodified field descriptor
     value is used. The command

          LC_ALL=language locale -ck era era_year era_d_fmt alt_digit

     displays the keywords and their values in the specified language (see
     locale(1)).

                Alternate appropriate date and time representation.

                The name of the base year in alternate representation.
          %Ex      Alternate date representation.

          %Ey      Offset from  (year only) in the alternate
                    representation.

          %EY      Full alternate year representation.

          %Od      Day of month using the alternate numeric symbols.

          %Oe      Day of month using the alternate numeric symbols with
                    leading space-character fill if applicable.

Hewlett-Packard Company           - 5 -  HP-UX Release 11i: November 2000

date(1)                                                            date(1)

          %OH      Hour (24-hour clock) using the alternate numeric
                    symbols.

          %OI      Hour (12-hour clock) using the alternate numeric
                    symbols.

          %Om      Month using the alternate numeric symbols.

          %OM      Minutes using the alternate numeric symbols.

          %OS      Seconds using the alternate numeric symbols.

          %OU      Week number of the year (Sunday is the first day of the
                    week) using the alternate numeric symbols.

          %Ow      Weekday as number using the alternate numeric symbols
                    (Sunday=0).

          %OW      Weekday number of the year (Monday is the first day of
                    the week) using the alternate numeric symbols.

          %Oy      Year (offset from %C) in alternate representation.

   Field Width and Precision
     An optional field width and precision specification can immediately
     follow the initial % of a formatting directive in the following order:

          [-|0]width The decimal digit string width specifies a minimum
                      field width in which the result of the conversion is
                      right- or left-justified. The default is right-
                      justified with space padding on the left. If the
                      string starts with "-", the result is left-justified
                      with space padding on the right. If the string
                      starts with "0", the result is right-justified and
                      padded with zeros on the left.

          .prec      The decimal digit string prec specifies the minimum
                      number of digits to appear for the d, H, I, j, m, M,
                      o, S, U, w, W, y, and Y numeric directives. If a
                      directive supplies fewer digits than specified by the
                      precision, it will be expanded with leading zeros.

                      prec specifies the maximum number of characters to be
                      used from the a, A, b, B, c, D, E, F, h, n, N, p, r,
                      t, T, x, X, z, Z, and % text directives. If a
                      directive supplies more characters than specified by
                      the precision, excess characters are truncated on the
                      right.

     If no field width or precision is specified for a d, H, I, m, M, S, U,
     W, or y directive, the default is .2; for the j directive, the default

Hewlett-Packard Company           - 6 -  HP-UX Release 11i: November 2000

date(1)                                                            date(1)

     is .3; for Y, the default is .4; for w, the default is .1.
EXTERNAL INFLUENCES
   Environment Variables
     LC_CTYPE determines the interpretation of the bytes within the format
     string as single- and/or multi-byte characters.

     LC_NUMERIC determines the characters used to form numbers for those
     directives that produce numbers in the output. The characters used
     are those defined by alt_digit (see locale(1) and ALT_DIGIT in
     langinfo(5)).

     LC_TIME determines the content (for example, the weekday names
     produced by the %a directive) and format (for example, the current
     time representation produced by the %X directive) of date and time
     strings output by the date command.

     LC_MESSAGES determines the language in which messages (other than the
     date and time strings) are displayed.

     If LC_CTYPE, LC_NUMERIC, LC_TIME, or LC_MESSAGES is not specified or
     is null, it defaults to the value of LANG.

     If LANG is not specified or is null, it defaults to C (see lang(5)).

     If any internationalization variable contains an invalid setting, all
     internationalization variables default to C (see environ(5)).

     TZ determines the conversion between the system time in UTC and the
     time in the user's local time zone. See environ(5) and tztab(4). TZ
     also determines the content (that is, the time-zone name produced by
     the %z and %Z directives) of date and time strings output by the date
     command.

     If TZ is not set or is set to the empty string, its default value is
     EST5EDT.

   International Code Set Support
     Single- and multi-byte character code sets are supported.

DIAGNOSTICS
     The following messages may be displayed.

     bad conversion

             The date/time specification is syntactically incorrect. Check
             it against the usage and for the correct range of each of the
             digit-pairs.

     bad format character - c

Hewlett-Packard Company           - 7 -  HP-UX Release 11i: November 2000

date(1)                                                            date(1)

             The character c is not a valid format directive, field width
             specifier, or precision specifier.

     do you really want to run time backwards?[yes/no]

             The date/time you specified is earlier than the current clock
             value. Type yes (or the equivalent for your locale) to set
             the clock backwards; anything else to cancel the command.

     no permission

             You need the superuser privilege to change the date.

EXAMPLES
   Date in Different Languages
     Display the date. In this example, the TZ environment variable
     contains PST8PDT, and the language environment variables are set as
     noted.

     date   -> Fri Aug 20 15:03:37 PDT 1993 <- C (default)
     date -u -> Fri Aug 20 22:03:37 UTC 1993 <- C (default)
     date   -> Fri, Aug 20, 1993 03:03:37 PM <- en_US.roman8 (U.S. English)
     date   -> Fri. 20 Aug, 1993 03:03:37 PM <- en_GB.roman8 (U.K. English)
     date   -> 20/08/1993 15.47.47          <- pt_PT.roman8 (Portuguese)

   Set Date
     Set the date to Oct 8, 12:45 a.m.

          date 10080045

   Display Formatted Date
     Display the current date and time using a format. Note the use of
     quotation marks due to the blanks in the format.

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

     The output resembles the following:

          DATE: 10/08/87
          TIME: 12:45:05

   Display Formatted Date Using Local Language Conversion
     With the date as set in the "Set Date" example above and LC_TIME set
     to de_De.roman8 (German):

          date +'%-4.4h %2.1d %H:%M'

     generates output similar to:

          Okt  8 12:45

Hewlett-Packard Company           - 8 -  HP-UX Release 11i: November 2000

date(1)                                                            date(1)

     where the month field is four characters long, flush-left, and space-
     padded on the right if the month name is shorter than four characters.
     The day field is two characters long, with leading zeros suppressed.

WARNINGS
     The former HP-UX format directive A has been changed to W for ANSI
     compatibility.

     Changing the date while the system is running in multiuser mode should
     be avoided to prevent disrupting user-scheduled and time sensitive
     programs and processes. Also, changing the date can cause make(1) and
     the SCCS and cron(1M) subsystems to behave in an unexpected manner.
     The cron daemon should be killed prior to setting the date backwards,
     then restarted. SCCS files should be checked with the val command
     (see val(1)) if deltas have been made while the clock was wrongly set.

     The following formatting directives may be deleted from future
     releases: %E, %F, %o, %z.

     Currently, the maximum date supported is December 31, 2037 23:59:00
     UTC.

AUTHOR
     date was developed by AT&T and HP.

FILES
     /var/adm/wtmp

SEE ALSO
     locale(1), stime(2), ctime(3C), strftime(3C), tztab(4), environ(5),
     lang(5), langinfo(5).

STANDARDS CONFORMANCE
     date: SVID2, SVID3, XPG2, XPG3, XPG4, POSIX.2

Hewlett-Packard Company           - 9 -  HP-UX Release 11i: November 2000