1.\" $NetBSD: utimes.2,v 1.30 2011/10/25 09:26:53 wiz Exp $ 2.\" 3.\" Copyright (c) 1990, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. Neither the name of the University nor the names of its contributors 15.\" may be used to endorse or promote products derived from this software 16.\" without specific prior written permission. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 19.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28.\" SUCH DAMAGE. 29.\" 30.\" @(#)utimes.2 8.1 (Berkeley) 6/4/93 31.\" 32.Dd August 17, 2011 33.Dt UTIMES 2 34.Os 35.Sh NAME 36.Nm utimes , 37.Nm lutimes , 38.Nm futimes , 39.Nm futimens , 40.Nm utimensat 41.Nd set file access and modification times 42.Sh LIBRARY 43.Lb libc 44.Sh SYNOPSIS 45.In sys/time.h 46.Ft int 47.Fn utimes "const char *path" "const struct timeval times[2]" 48.Ft int 49.Fn lutimes "const char *path" "const struct timeval times[2]" 50.Ft int 51.Fn futimes "int fd" "const struct timeval times[2]" 52.Ft int 53.Fn futimens "int fd" "const struct timespec times[2]" 54.Ft int 55.Fn utimensat "int fd" "const char *path" "const struct timespec times[2]" "int flag" 56.Sh DESCRIPTION 57The access and modification times of the file named by 58.Fa path 59or referenced by 60.Fa fd 61are changed as specified by the argument 62.Fa times . 63.Pp 64If 65.Fa times 66is 67.Dv NULL , 68the access and modification times are set to the current time. 69The caller must be the owner of the file, have permission to 70write the file, or be the super-user. 71.Pp 72If 73.Fa times 74is 75.Pf non- Dv NULL , 76it is assumed to point to an array of two timeval structures. 77The access time is set to the value of the first element, and the 78modification time is set to the value of the second element. 79For file systems that support file birth (creation) times (such as 80UFS2), the birth time will be set to the value of the second element 81if the second element is older than the currently set birth time. 82To set both a birth time and a modification time, two calls are 83required; the first to set the birth time and the second to set 84the (presumably newer) modification time. 85Ideally a new system call will be added that allows the setting of 86all three times at once. 87The caller must be the owner of the file or be the super-user. 88.Pp 89In either case, the inode-change-time of the file is set to the current 90time. 91.Pp 92.Fn lutimes 93is like 94.Fn utimes 95except in the case where the named file is a symbolic link, 96in which case 97.Fn lutimes 98changes the access and modification times of the link, 99while 100.Fn utimes 101changes the times of the file the link references. 102.Pp 103.Fn futimens 104is like 105.Fn futimes 106except that time is specified with nanosecond instead of microseconds. 107.Pp 108.Fn utimensat 109also allows time to be specifed with nanoseconds. 110When it operates on a symbolic link, it will change the target's time if 111.Ar follow 112is unset. 113If 114.Ar follow 115is set to 116.Dv AT_SYMLINK_NOFOLLOW , 117the symbolic link's dates are changed. 118.Pp 119The nanosecond fields for 120.Fn futimens 121and 122.Fn utimensat 123can be set to the special value 124.Dv UTIME_NOW 125to set the current time, or to 126.Dv UTIME_OMIT 127to let the time unchanged (this allows changing access time but not 128modification time, and vice-versa). 129.Pp 130.Fn utimensat 131is partially implemented. 132It will return 133.Er ENOSYS 134for 135.Fa fd 136values different than 137.Dv AT_FDCWD . 138.Sh RETURN VALUES 139Upon successful completion, a value of 0 is returned. 140Otherwise, a value of \-1 is returned and 141.Va errno 142is set to indicate the error. 143.Sh ERRORS 144.Fn utimes , 145.Fn lutimes , 146and 147.Fn utimensat 148will fail if: 149.Bl -tag -width Er 150.It Bq Er EACCES 151Search permission is denied for a component of the path prefix; 152or the 153.Fa times 154argument is 155.Dv NULL 156and the effective user ID of the process does not 157match the owner of the file, and is not the super-user, and write 158access is denied. 159.It Bq Er EFAULT 160.Fa path 161or 162.Fa times 163points outside the process's allocated address space. 164.It Bq Er EIO 165An I/O error occurred while reading or writing the affected inode. 166.It Bq Er ELOOP 167Too many symbolic links were encountered in translating the pathname. 168.It Bq Er ENAMETOOLONG 169A component of a pathname exceeded 170.Brq Dv NAME_MAX 171characters, or an entire path name exceeded 172.Brq Dv PATH_MAX 173characters. 174.It Bq Er ENOENT 175The named file does not exist. 176.It Bq Er ENOTDIR 177A component of the path prefix is not a directory. 178.It Bq Er EPERM 179The 180.Fa times 181argument is not 182.Dv NULL 183and the calling process's effective user ID 184does not match the owner of the file and is not the super-user. 185.It Bq Er EROFS 186The file system containing the file is mounted read-only. 187.El 188.Pp 189.Fn futimes 190and 191.Fn futimens 192will fail if: 193.Bl -tag -width Er 194.It Bq Er EACCES 195The 196.Fa times 197argument is 198.Dv NULL 199and the effective user ID of the process does not 200match the owner of the file, and is not the super-user, and write 201access is denied. 202.It Bq Er EBADF 203.Fa fd 204does not refer to a valid descriptor. 205.It Bq Er EFAULT 206.Fa times 207points outside the process's allocated address space. 208.It Bq Er EIO 209An I/O error occurred while reading or writing the affected inode. 210.It Bq Er EPERM 211The 212.Fa times 213argument is not 214.Dv NULL 215and the calling process's effective user ID 216does not match the owner of the file and is not the super-user. 217.It Bq Er EROFS 218The file system containing the file is mounted read-only. 219.El 220.Sh SEE ALSO 221.Xr stat 2 , 222.Xr utime 3 , 223.Xr symlink 7 224.Sh STANDARDS 225The 226.Fn utimes 227function conforms to 228.St -p1003.1-2001 . 229It was however marked as legacy in the 230.St -p1003.1-2004 231revision. 232.Fn futimens 233and 234.Fn utimensat 235functions conform to 236.St -p1003.1-2008 . 237.Sh HISTORY 238The 239.Fn utimes 240function call appeared in 241.Bx 4.2 . 242The 243.Fn futimes 244function call appeared in 245.Nx 1.2 . 246The 247.Fn lutimes 248function call appeared in 249.Nx 1.3 . 250Birthtime setting support was added in 251.Nx 5.0 . 252.Fn futimens 253and 254.Fn utimensat 255functions calls appreared in 256.Nx 6.0 . 257.Sh BUGS 258.Fn utimensat 259is partially implemented. 260