1.\" Copyright (c) 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" This code is derived from software contributed to Berkeley by 5.\" the Institute of Electrical and Electronics Engineers, Inc. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in the 14.\" documentation and/or other materials provided with the distribution. 15.\" 3. Neither the name of the University nor the names of its contributors 16.\" may be used to endorse or promote products derived from this software 17.\" without specific prior written permission. 18.\" 19.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29.\" SUCH DAMAGE. 30.\" 31.\" @(#)touch.1 8.3 (Berkeley) 4/28/95 32.\" $FreeBSD$ 33.\" 34.Dd June 1, 2018 35.Dt TOUCH 1 36.Os 37.Sh NAME 38.Nm touch 39.Nd change file access and modification times 40.Sh SYNOPSIS 41.Nm 42.Op Fl A Ar [-][[hh]mm]SS 43.Op Fl achm 44.Op Fl r Ar file 45.Op Fl t Ar [[CC]YY]MMDDhhmm[.SS] 46.Op Fl d Ar YYYY-MM-DDThh:mm:SS[.frac][tz] 47.Ar 48.Sh DESCRIPTION 49The 50.Nm 51utility sets the modification and access times of files. 52If any file does not exist, it is created with default permissions. 53.Pp 54By default, 55.Nm 56changes both modification and access times. 57The 58.Fl a 59and 60.Fl m 61flags may be used to select the access time or the modification time 62individually. 63Selecting both is equivalent to the default. 64By default, the timestamps are set to the current time. 65The 66.Fl d 67and 68.Fl t 69flags explicitly specify a different time, and the 70.Fl r 71flag specifies to set the times those of the specified file. 72The 73.Fl A 74flag adjusts the values by a specified amount. 75.Pp 76The following options are available: 77.Bl -tag -width Ds 78.It Fl A 79Adjust the access and modification time stamps for the file by the 80specified value. 81This flag is intended for use in modifying files with incorrectly set 82time stamps. 83.Pp 84The argument is of the form 85.Dq [-][[hh]mm]SS 86where each pair of letters represents the following: 87.Pp 88.Bl -tag -width Ds -compact -offset indent 89.It Ar - 90Make the adjustment negative: the new time stamp is set to be before 91the old one. 92.It Ar hh 93The number of hours, from 00 to 99. 94.It Ar mm 95The number of minutes, from 00 to 59. 96.It Ar SS 97The number of seconds, from 00 to 59. 98.El 99.Pp 100The 101.Fl A 102flag implies the 103.Fl c 104flag: if any file specified does not exist, it will be silently ignored. 105.It Fl a 106Change the access time of the file. 107The modification time of the file is not changed unless the 108.Fl m 109flag is also specified. 110.It Fl c 111Do not create the file if it does not exist. 112The 113.Nm 114utility does not treat this as an error. 115No error messages are displayed and the exit value is not affected. 116.It Fl d 117Change the access and modification times to the specified date time instead 118of the current time of day. 119The argument is of the form 120.Dq YYYY-MM-DDThh:mm:SS[.frac][tz] 121where the letters represent the following: 122.Bl -tag -width Ds -compact -offset indent 123.It Ar YYYY 124At least four decimal digits representing the year. 125.It Ar MM , Ar DD , Ar hh , Ar mm , Ar SS 126As with 127.Fl t 128time. 129.It Ar T 130The letter 131.Li T 132or a space is the time designator. 133.It Ar .frac 134An optional fraction, consisting of a period or a comma followed by one or 135more digits. 136The number of significant digits depends on the kernel configuration and the 137filesystem, and may be zero. 138.It Ar tz 139An optional letter 140.Li Z 141indicating the time is in 142.Tn UTC . 143Otherwise, the time is assumed to be in local time. 144Local time is affected by the value of the 145.Ev TZ 146environment variable. 147.El 148.It Fl h 149If the file is a symbolic link, change the times of the link 150itself rather than the file that the link points to. 151Note that 152.Fl h 153implies 154.Fl c 155and thus will not create any new files. 156.It Fl m 157Change the modification time of the file. 158The access time of the file is not changed unless the 159.Fl a 160flag is also specified. 161.It Fl r 162Use the access and modifications times from the specified file 163instead of the current time of day. 164.It Fl t 165Change the access and modification times to the specified time instead 166of the current time of day. 167The argument is of the form 168.Dq [[CC]YY]MMDDhhmm[.SS] 169where each pair of letters represents the following: 170.Pp 171.Bl -tag -width Ds -compact -offset indent 172.It Ar CC 173The first two digits of the year (the century). 174.It Ar YY 175The second two digits of the year. 176If 177.Dq YY 178is specified, but 179.Dq CC 180is not, a value for 181.Dq YY 182between 69 and 99 results in a 183.Dq CC 184value of 19. 185Otherwise, a 186.Dq CC 187value of 20 is used. 188.It Ar MM 189The month of the year, from 01 to 12. 190.It Ar DD 191the day of the month, from 01 to 31. 192.It Ar hh 193The hour of the day, from 00 to 23. 194.It Ar mm 195The minute of the hour, from 00 to 59. 196.It Ar SS 197The second of the minute, from 00 to 60. 198.El 199.Pp 200If the 201.Dq CC 202and 203.Dq YY 204letter pairs are not specified, the values default to the current 205year. 206If the 207.Dq SS 208letter pair is not specified, the value defaults to 0. 209.El 210.Sh EXIT STATUS 211.Ex -std 212.Sh COMPATIBILITY 213The obsolescent form of 214.Nm , 215where a time format is specified as the first argument, is supported. 216When no 217.Fl r 218or 219.Fl t 220option is specified, there are at least two arguments, and the first 221argument is a string of digits either eight or ten characters in length, 222the first argument is interpreted as a time specification of the form 223.Dq MMDDhhmm[YY] . 224.Pp 225The 226.Dq MM , 227.Dq DD , 228.Dq hh 229and 230.Dq mm 231letter pairs are treated as their counterparts specified to the 232.Fl t 233option. 234If the 235.Dq YY 236letter pair is in the range 39 to 99, the year is set to 1939 to 1999, 237otherwise, the year is set in the 21st century. 238.Sh SEE ALSO 239.Xr utimensat 2 240.Sh STANDARDS 241The 242.Nm 243utility is expected to be a superset of the 244.St -p1003.2 245specification. 246.Sh HISTORY 247A 248.Nm 249utility appeared in 250.At v7 . 251