Manual Pages for UNIX Operating System command usage for man settime

User Commands                                            touch(1)



NAME
     touch, settime - change file access and modification times

SYNOPSIS
     touch [-acm] [-r ref_file | -t time | -d date_time] file...


     touch [-acm] [time_spec] file...


     settime [-f ref_file] [time_spec] file...


DESCRIPTION
     The touch utility sets the access and modification times  of
     each  file.  The  file  operand  is  created  if it does not
     already exist.


     The time used can be specified by -t time, by -d  date_time,
     by  the  corresponding time fields of the file referenced by
     -r ref_file, or by the time_spec operand. If none  of  these
     are specified, touch uses the current time.


     If neither the  -a  nor  -m  options  are  specified,  touch
     updates both the modification and access times.


     A user with write access to a file, but who is not the owner
     of the file or a super-user, can change the modification and
     access times of that file only to the current time. Attempts
     to set a specific time with touch results in an error.


     The settime utility is equivalent to  touch  -c  [time_spec]
     file.

OPTIONS
     The following options are supported in the touch and settime
     utilities:

  touch
     The following options are supported for the touch utility:

     -a

         Changes the access time of file.  Does  not  change  the
         modification time unless -m is also specified.






SunOS 5.11           Last change: 9 Sep 2009                    1






User Commands                                            touch(1)



     -c

         Does not create a specified file if it does  not  exist.
         Does  not  write any diagnostic messages concerning this
         condition.


     -d date_time

         Uses the specified  date_time  instead  of  the  current
         time. The option-argument must be a string of the form:

           YYYY-MM-DDThh:mm:SS[.frac][tz]


         or

           YYYY-MM-DDThh:mm:SS[,frac][tz]


         where

             o    YYYY is at least four decimal digits giving the
                  year

             o    MM, DD, hh, mm, and SS are as with -t time

             o    T is either the letter  T  or  a  single  SPACE
                  character

             o    [.frac] and [,frac]  are  either  empty,  or  a
                  period  (.)  or  a comma (,) respectively, fol-
                  lowed by one or more decimal digits, specifying
                  a fractional second

             o    [tz] is either empty, signifying local time, or
                  the letter Z, signifying UTC. If [tz] is empty,
                  the resulting time is affected by the value  of
                  the TZ environment variable


     -m

         Changes the modification time of file. Does  not  change
         the access time unless -a is also specified.


     -r ref_file

         Uses the  corresponding  times  of  the  file  named  by
         ref_file instead of the current time.




SunOS 5.11           Last change: 9 Sep 2009                    2






User Commands                                            touch(1)



     -t time

         Uses the specified time instead  of  the  current  time.
         time is a decimal number of the form:

           [[CC]YY]MMDDhhmm[.SS]


         where each two digits represent the following:

         MM

             The month of the year [01-12].


         DD

             The day of the month [01-31].


         hh

             The hour of the day [00-23].


         mm

             The minute of the hour [00-59].


         CC

             The first two digits of the year.


         YY

             The second two digits of the year.


         SS

             The second of the minute [00-61].

         Both CC and YY are optional. If neither  is  given,  the
         current  year  is assumed. If YY is specified, but CC is
         not, CC is derived as follows:








SunOS 5.11           Last change: 9 Sep 2009                    3






User Commands                                            touch(1)



         ____________________________________________________________
        |          If YY is:                    CC becomes:         |
        |___________________________________________________________|
        | 69-99                         19                          |
        | 00-38                         20                          |
        | 39-68                         ERROR                       |
        |___________________________________________________________|

         The resulting time is affected by the value  of  the  TZ
         environment  variable.  If the resulting time value pre-
         cedes the Epoch, touch exits immediately with  an  error
         status. The range of valid times is the Epoch to January
         18, 2038.

         The range for SS is [00-61] rather than [00-59]  because
         of  leap  seconds.  If SS is 60 or 61, and the resulting
         time, as affected by the TZ environment  variable,  does
         not refer to a leap second, the resulting time is one or
         two seconds after a time where SS is 59. If  SS  is  not
         given, it is assumed to be 0.


  settime
     The following option is supported for the settime utility:

     -f ref_file

         Uses the  corresponding  times  of  the  file  named  by
         ref_file instead of the current time.


OPERANDS
     The following operands are supported for the touch and  set-
     time utilities:

     file

         A path name of a file whose times are to be modified.


     time_spec

         Uses the specified  time_spec  instead  of  the  current
         time. This operand is a decimal number of the form:

           MMDDhhmm[YY]


         where each two digits represent the following:

         MM




SunOS 5.11           Last change: 9 Sep 2009                    4






User Commands                                            touch(1)



             The month of the year [01-12].


         DD

             The day of the month [01-31].


         hh

             The hour of the day [00-23].


         mm

             The minute of the hour [00-59].


         YY

             The second two digits of the year.

             YY is optional. If it is omitted, the  current  year
             is  assumed. If YY is specified, the year is derived
             as follows:




         ____________________________________________________________
        |             YY                     Corresponding Year     |
        | 69-99                         1969-1999                   |
        | 00-38                         2000-2038                   |
        | 39-68                         ERROR                       |
        |___________________________________________________________|

         If no -d, -r, or -toption is  specified,  at  least  two
         operands  are  specified,  and  the  first operand is an
         eight- or ten-digit decimal integer, the  first  operand
         is  assumed  to  be  a time_spec operand. Otherwise, the
         first operand is assumed to be a file operand.


USAGE
     See largefile(5) for the  description  of  the  behavior  of
     touch  when  encountering  files  greater than or equal to 2
     Gbyte ( 2^31 bytes).

ENVIRONMENT VARIABLES
     See environ(5) for descriptions of the following environment
     variables  that affect the execution of touch: LANG, LC_ALL,
     LANG, LC_ALL, LC_CTYPE, LC_MESSAGES, and NLSPATH.



SunOS 5.11           Last change: 9 Sep 2009                    5






User Commands                                            touch(1)



     TZ

         Determine the timezone to be used for  interpreting  the
         time  or  date_time  option-argument  or  the  time_spec
         operand.


EXIT STATUS
     The following exit values are returned:

     0

         The  touch  utility  executed   successfully   and   all
         requested changes were made.


     >0

         An error occurred. The touch utility returned the number
         of  files  for which the times could not be successfully
         modified.


ATTRIBUTES
     See attributes(5) for descriptions of the  following  attri-
     butes:



     ____________________________________________________________
    |       ATTRIBUTE TYPE        |       ATTRIBUTE VALUE       |
    |_____________________________|_____________________________|
    | Availability                | SUNWcs                      |
    |_____________________________|_____________________________|
    | CSI                         | Enabled                     |
    |_____________________________|_____________________________|
    | Interface Stability         | Committed                   |
    |_____________________________|_____________________________|
    | Standard                    | See standards(5).           |
    |_____________________________|_____________________________|


SEE ALSO
     futimens(2),  stat(2),  attributes(5),  environ(5),   large-
     file(5), standards(5)

NOTES
     Users familiar with the BSD environment find  that  for  the
     touch utility, the -f option is accepted but ignored. The -f
     option is unnecessary because touch succeeds for  all  files
     owned  by  the  user  regardless  of  the permissions on the
     files.



SunOS 5.11           Last change: 9 Sep 2009                    6