touch



TOUCH(1)                    General Commands Manual                   TOUCH(1)


NAME

     touch - change file access and modification times


SYNOPSIS

     touch [-acm] [-d ccyy-mm-ddTHH:MM:SS[.frac][Z]] [-r file]
           [-t [[cc]yy]mmddHHMM[.SS]] file ...


DESCRIPTION

     The touch utility sets the modification and access times of files to the
     current time of day.  If the file doesn't exist, it is created with
     default permissions.

     The options are as follows:

     -a      Change the access time of the file.  The modification time of the
             file is not changed unless the -m flag is also specified.

     -c      Do not create the file if it does not exist.  The touch utility
             does not treat this as an error.  No error messages are displayed
             and the exit value is not affected.

     -d ccyy-mm-ddTHH:MM:SS[.frac][Z]
             Change the access and modification times to the specified time,
             in a format compliant with the ISO 8601 standard.  The parts of
             the argument represent the following:

                   ccyy   Year.
                   mm     Month: a number from 1 to 12.
                   dd     Day: a number from 1 to 31.
                   T      Either the capital letter `T' or a single space.  If
                          a space is used, the argument should be quoted to
                          prevent the shell from splitting it into multiple
                          words.
                   HH     Hour: a number from 0 to 23.
                   MM     Minute: a number from 0 to 59.
                   SS     Second: a number from 0 to 60 (permitting a leap
                          second).
                   frac   The decimal fraction of the second, either a period
                          or comma, followed by one or more decimal digits.
                   Z      The timezone specifier: a capital letter `Z'
                          indicating that the time is in UTC.  If not
                          specified, the time is in the local timezone.

     -m      Change the modification time of the file.  The access time of the
             file is not changed unless the -a flag is also specified.

     -r file
             Use the access and modification times from the specified file
             instead of the current time of day.

     -t [[cc]yy]mmddHHMM[.SS]
             Change the access and modification times to the specified time,
             where the parts of the argument represent the following:

                   ccyy    Year.  If yy is specified, but cc is not, a value
                           for yy between 69 and 99 results in a cc value of
                           19.  Otherwise, a cc value of 20 is used.
                   mm      Month: a number from 1 to 12.
                   dd      Day: a number from 1 to 31.
                   HH      Hour: a number from 0 to 23.
                   MM      Minute: a number from 0 to 59.
                   SS      Second: a number from 0 to 60 (permitting a leap
                           second), preceded by a period.  The default is 0.


EXIT STATUS

     The touch utility exits 0 on success, and >0 if an error occurs.


SEE ALSO

     date(1)


STANDARDS

     The touch utility is compliant with the IEEE Std 1003.1-2008
     (``POSIX.1'') specification.

     The obsolescent form of touch, where a time format is specified as the
     first argument, is supported.  When no -d, -r, or -t option is specified,
     there are at least two arguments, and the first argument is a string of
     digits either eight or ten characters in length, the first argument is
     interpreted as a time specification of the form ``mmddHHMM[yy]''.


HISTORY

     A touch utility appeared in Version 7 AT&T UNIX.

OpenBSD 5.9                   September 25, 2015                   OpenBSD 5.9

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