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touch(1)                         User Commands                        touch(1)



NAME
       touch, settime - change file access and modification times

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

       touch [-acm] [date_time] file...

       settime [-f ref_file] [date_time] 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  the  corresponding  time
       fields of the file referenced by -r ref_file, or by the date_time oper-
       and. If none of these are specified, touch uses the current  time  (the
       value returned by the time(2) function).

       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 will result in an error.

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



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



       -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.



       -t time         Uses the specified time instead of  the  current  time.
                       time will be 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 will be assumed. If YY is  specified,  but
                       CC is not, CC will be derived as follows:



                       tab()  box;  lw(2.750000i)  lw(2.750000i) cw(2.750000i)
                       cw(2.750000i).  If YY is:CC  becomes:  69-9919  00-3820
                       39-68ERROR

                       The resulting time will be affected by the value of the
                       TZ environment variable. If the  resulting  time  value
                       precedes the Epoch, touch will exit 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 will  be
                       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 settime utili-
       ties:

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



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


                       MMDDhhmm[YY]

                       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].



                       YY       The second two digits of the year.

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





                       tab()  box;  lw(2.750000i)  lw(2.750000i) cw(2.750000i)
                       cw(2.750000i).   YYCorresponding  Year   69-991969-1999
                       00-382000-2038 39-68ERROR

                       If  no  -r  option is specified, no -t option is speci-
                       fied, at least two  operands  are  specified,  and  the
                       first  operand  is an eight- or ten-digit decimal inte-
                       ger,  the  first  operand  will  be  assumed  to  be  a
                       date_time operand. Otherwise, the first operand will be
                       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.

       TZ       Determine  the  timezone  to be used for interpreting the time
                option-argument or the date_time 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 attributes:


       tab()    allbox;    cw(2.750000i)|     cw(2.750000i)     lw(2.750000i)|
       lw(2.750000i).    ATTRIBUTE   TYPEATTRIBUTE  VALUE  AvailabilitySUNWcsu
       CSIenabled Interface StabilityStandard


SEE ALSO
       time(2), attributes(5), environ(5), largefile(5), standards(5)

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



SunOS 5.10                        22 Jun 2001                         touch(1)