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TOUCH(1) NetBSD General Commands Manual TOUCH(1)
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touch -- change file access and modification times
touch [-acfhm] [-d human-datetime] [--date human-datetime] [-r file]
[--reference file] [-t datetime] file ...
The touch utility changes the access and modification times of files to
the current time of day. If the file doesn't exist, it is created with
The following options are available:
-a Change the access time of the file. The modification
time of the file is not changed unless the -m flag is
-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
Parse human-datetime using the human datetime parser
-f This flag has no effect; it is accepted for compati-
-h If file is a symbolic link, access and/or modification
time of the link is changed. This option implies -c.
-m Change the modification time of the file. The access
time of the file is not changed unless the -a flag is
--reference file Use the access and modifications times from file
instead of the current time of day.
-t datetime Change the access and modification times to the speci-
fied time. The argument datetime should be in the
form ``[[CC]YY]MMDDhhmm[.SS]'' where each pair of let-
ters represents the following:
CC The first two digits of the year (the
YY The second two digits of the year. If
``YY'' is specified, but ``CC'' is not,
a value for ``YY'' between 69 and 99
results in a ``CC'' value of 19. Other-
wise, a ``CC'' value of 20 is used.
MM The month of the year, from 1 to 12.
DD The day of the month, from 1 to 31.
hh The hour of the day, from 0 to 23.
mm The minute of the hour, from 0 to 59.
SS The second of the minute, from 0 to 60
(permitting leap seconds). If SS is 60
and the resulting time, as affected by
the TZ environment variable, does not
refer to a leap second, the resulting
time is one second after a time where SS
is 59. If SS is not given a value, it
is assumed to be zero.
If the ``CC'' and ``YY'' letter pairs are not speci-
fied, the values default to the current year. If the
``SS'' letter pair is not specified, the value
defaults to 0.
The -d, -r, and -t options are mutually exclusive. If more than one of
these options is present, the last one is used.
TZ The timezone to be used for interpreting the datetime argument of
the -t option.
The touch utility exits 0 on success, and >0 if an error occurs.
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]''.
The ``MM'', ``DD'', ``hh'' and ``mm'' letter pairs are treated as their
counterparts specified to the -t option. If the ``YY'' letter pair is in
the range 69 to 99, the year is set to 1969 to 1999, otherwise, the year
is set in the 21st century.
The touch utility is expected to be a superset of the IEEE Std 1003.2
A touch utility appeared in Version 7 AT&T UNIX.
A symbolic link can't be a reference file of access and/or modification
NetBSD 9.99 December 24, 2016 NetBSD 9.99