+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\" @(#)touch.1 8.2 (Berkeley) 12/30/93
+.\"
+.Dd December 30, 1993
+.Dt TOUCH 1
+.Os
+.Sh NAME
+.Nm touch
+.Nd change file access and modification times
+.Sh SYNOPSIS
+.Nm touch
+.Op Fl acfm
+.Op Fl r Ar file
+.Op Fl t [[CC]YY]MMDDhhmm[.SS]
+.Ar file ...
+.Sh DESCRIPTION
+The
+.Nm 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.
+.Pp
+The following options are available:
+.Bl -tag -width Ds
+.It Fl a
+Change the access time of the file.
+The modification time of the file is not changed unless the
+.Fl m
+flag is also specified.
+.It Fl c
+Do not create the file if it does not exist.
+The
+.Nm touch
+utility does not treat this as an error.
+No error messages are displayed and the exit value is not affected.
+.It Fl f
+Attempt to force the update, even if the file permissions do not
+currently permit it.
+.It Fl m
+Change the modification time of the file.
+The access time of the file is not changed unless the
+.Fl a
+flag is also specified.
+.It Fl r
+Use the access and modifications times from the specified file
+instead of the current time of day.
+.It Fl t
+Change the access and modification times to the specified time.
+The argument should be in the form
+.Dq [[CC]YY]MMDDhhmm[.SS]
+where each pair of letters represents the following:
+.Pp
+.Bl -tag -width Ds -compact -offset indent
+.It Ar CC
+The first two digits of the year (the century).
+.It Ar YY
+The second two digits of the year.
+If
+.Dq YY
+is specified, but
+.Dq CC
+is not, a value for
+.Dq YY
+between 69 and 99 results in a
+.Dq YY
+value of 19.
+Otherwise, a
+.Dq YY
+value of 20 is used.
+.It Ar MM
+The month of the year, from 1 to 12.
+.It Ar DD
+the day of the month, from 1 to 31.
+.It Ar hh
+The hour of the day, from 0 to 23.
+.It Ar mm
+The minute of the hour, from 0 to 59.
+.It Ar SS
+The second of the minute, from 0 to 61.
+.El
+.Pp
+If the
+.Dq CC
+and
+.Dq YY
+letter pairs are not specified, the values default to the current
+year.
+If the
+.Dq SS
+letter pair is not specified, the value defaults to 0.
+.El
+.Pp
+The
+.Nm touch
+utility exits 0 on success, and >0 if an error occurs.
+.Sh SEE ALSO
+.Xr utimes 2
+.Sh COMPATIBILITY
+The obsolescent form of
+.Nm touch ,
+where a time format is specified as the first argument, is supported.
+When no
+.Fl r
+or
+.Fl 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
+.Dq MMDDhhmm[YY] .
+.Pp
+The
+.Dq MM ,
+.Dq DD ,
+.Dq hh
+and
+.Dq mm
+letter pairs are treated as their counterparts specified to the
+.Fl t
+option.
+If the
+.Dq 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.
+.Sh HISTORY
+A
+.Nm touch
+command appeared in
+.At v7 .
+.Sh STANDARDS
projects / unix-history / blobdiff