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utime.html
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<!-- Creator : groff version 1.22.4 -->
<!-- CreationDate: Wed Jan 29 11:25:47 2020 -->
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta name="generator" content="groff -Thtml, see www.gnu.org">
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
<meta name="Content-Style" content="text/css">
<style type="text/css">
p { margin-top: 0; margin-bottom: 0; vertical-align: top }
pre { margin-top: 0; margin-bottom: 0; vertical-align: top }
table { margin-top: 0; margin-bottom: 0; vertical-align: top }
h1 { text-align: center }
</style>
<title>UTIME</title>
</head>
<body>
<h1 align="center">UTIME</h1>
<a href="#NAME">NAME</a><br>
<a href="#SYNOPSIS">SYNOPSIS</a><br>
<a href="#DESCRIPTION">DESCRIPTION</a><br>
<a href="#RETURN VALUE">RETURN VALUE</a><br>
<a href="#ERRORS">ERRORS</a><br>
<a href="#CONFORMING TO">CONFORMING TO</a><br>
<a href="#NOTES">NOTES</a><br>
<a href="#SEE ALSO">SEE ALSO</a><br>
<a href="#COLOPHON">COLOPHON</a><br>
<hr>
<h2>NAME
<a name="NAME"></a>
</h2>
<p style="margin-left:11%; margin-top: 1em">utime, utimes -
change file last access and modification times</p>
<h2>SYNOPSIS
<a name="SYNOPSIS"></a>
</h2>
<p style="margin-left:11%; margin-top: 1em"><b>#include
<sys/types.h> <br>
#include <utime.h></b></p>
<p style="margin-left:11%; margin-top: 1em"><b>int
utime(const char *</b><i>filename</i><b>, const struct
utimbuf *</b><i>times</i><b>);</b></p>
<p style="margin-left:11%; margin-top: 1em"><b>#include
<sys/time.h></b></p>
<p style="margin-left:11%; margin-top: 1em"><b>int
utimes(const char *</b><i>filename</i><b>, const struct
timeval</b> <i>times</i><b>[2]);</b></p>
<h2>DESCRIPTION
<a name="DESCRIPTION"></a>
</h2>
<p style="margin-left:11%; margin-top: 1em"><b>Note:</b>
modern applications may prefer to use the interfaces
described in <b>utimensat</b>(2).</p>
<p style="margin-left:11%; margin-top: 1em">The
<b>utime</b>() system call changes the access and
modification times of the inode specified by <i>filename</i>
to the <i>actime</i> and <i>modtime</i> fields of
<i>times</i> respectively.</p>
<p style="margin-left:11%; margin-top: 1em">If <i>times</i>
is NULL, then the access and modification times of the file
are set to the current time.</p>
<p style="margin-left:11%; margin-top: 1em">Changing
timestamps is permitted when: either the process has
appropriate privileges, or the effective user ID equals the
user ID of the file, or <i>times</i> is NULL and the process
has write permission for the file.</p>
<p style="margin-left:11%; margin-top: 1em">The
<i>utimbuf</i> structure is:</p>
<p style="margin-left:17%; margin-top: 1em">struct utimbuf
{ <br>
time_t actime; /* access time */ <br>
time_t modtime; /* modification time */ <br>
};</p>
<p style="margin-left:11%; margin-top: 1em">The
<b>utime</b>() system call allows specification of
timestamps with a resolution of 1 second.</p>
<p style="margin-left:11%; margin-top: 1em">The
<b>utimes</b>() system call is similar, but the <i>times</i>
argument refers to an array rather than a structure. The
elements of this array are <i>timeval</i> structures, which
allow a precision of 1 microsecond for specifying
timestamps. The <i>timeval</i> structure is:</p>
<p style="margin-left:17%; margin-top: 1em">struct timeval
{ <br>
long tv_sec; /* seconds */ <br>
long tv_usec; /* microseconds */ <br>
};</p>
<p style="margin-left:11%; margin-top: 1em"><i>times</i>[0]
specifies the new access time, and <i>times</i>[1] specifies
the new modification time. If <i>times</i> is NULL, then
analogously to <b>utime</b>(), the access and modification
times of the file are set to the current time.</p>
<h2>RETURN VALUE
<a name="RETURN VALUE"></a>
</h2>
<p style="margin-left:11%; margin-top: 1em">On success,
zero is returned. On error, -1 is returned, and <i>errno</i>
is set appropriately.</p>
<h2>ERRORS
<a name="ERRORS"></a>
</h2>
<table width="100%" border="0" rules="none" frame="void"
cellspacing="0" cellpadding="0">
<tr valign="top" align="left">
<td width="11%"></td>
<td width="9%">
<p style="margin-top: 1em"><b>EACCES</b></p></td>
<td width="2%"></td>
<td width="78%">
<p style="margin-top: 1em">Search permission is denied for
one of the directories in the path prefix of <i>path</i>
(see also <b>path_resolution</b>(7)).</p></td></tr>
<tr valign="top" align="left">
<td width="11%"></td>
<td width="9%">
<p><b>EACCES</b></p></td>
<td width="2%"></td>
<td width="78%">
<p><i>times</i> is NULL, the caller’s effective user
ID does not match the owner of the file, the caller does not
have write access to the file, and the caller is not
privileged (Linux: does not have either the
<b>CAP_DAC_OVERRIDE</b> or the <b>CAP_FOWNER</b>
capability).</p> </td></tr>
<tr valign="top" align="left">
<td width="11%"></td>
<td width="9%">
<p><b>ENOENT</b></p></td>
<td width="2%"></td>
<td width="78%">
<p><i>filename</i> does not exist.</p></td></tr>
<tr valign="top" align="left">
<td width="11%"></td>
<td width="9%">
<p><b>EPERM</b></p></td>
<td width="2%"></td>
<td width="78%">
<p><i>times</i> is not NULL, the caller’s effective
UID does not match the owner of the file, and the caller is
not privileged (Linux: does not have the <b>CAP_FOWNER</b>
capability).</p> </td></tr>
<tr valign="top" align="left">
<td width="11%"></td>
<td width="9%">
<p><b>EROFS</b></p></td>
<td width="2%"></td>
<td width="78%">
<p><i>path</i> resides on a read-only filesystem.</p></td></tr>
</table>
<h2>CONFORMING TO
<a name="CONFORMING TO"></a>
</h2>
<p style="margin-left:11%; margin-top: 1em"><b>utime</b>():
SVr4, POSIX.1-2001. POSIX.1-2008 marks <b>utime</b>() as
obsolete.</p>
<p style="margin-left:11%; margin-top: 1em"><b>utimes</b>():
4.3BSD, POSIX.1-2001.</p>
<h2>NOTES
<a name="NOTES"></a>
</h2>
<p style="margin-left:11%; margin-top: 1em">Linux does not
allow changing the timestamps on an immutable file, or
setting the timestamps to something other than the current
time on an append-only file.</p>
<h2>SEE ALSO
<a name="SEE ALSO"></a>
</h2>
<p style="margin-left:11%; margin-top: 1em"><b>chattr</b>(1),
<b>touch</b>(1), <b>futimesat</b>(2), <b>stat</b>(2),
<b>utimensat</b>(2), <b>futimens</b>(3), <b>futimes</b>(3),
<b>inode</b>(7)</p>
<h2>COLOPHON
<a name="COLOPHON"></a>
</h2>
<p style="margin-left:11%; margin-top: 1em">This page is
part of release 5.02 of the Linux <i>man-pages</i> project.
A description of the project, information about reporting
bugs, and the latest version of this page, can be found at
https://www.kernel.org/doc/man-pages/.</p>
<hr>
</body>
</html>