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<center><font size="2">The Open Group Base Specifications Issue 6<br>
IEEE Std 1003.1-2001<br>
Copyright &copy; 2001 The IEEE and The Open Group, All Rights reserved.</font></center>
<!--header end-->
<hr size="2" noshade>
<h4><a name="tag_03_327_01"></a>NAME</h4>
<blockquote>lchown - change the owner and group of a symbolic link</blockquote>
<h4><a name="tag_03_327_02"></a>SYNOPSIS</h4>
<blockquote class="synopsis">
<div class="box"><code><tt><sup>[<a href="javascript:open_code('XSI')">XSI</a>]</sup> <img src="../images/opt-start.gif" alt=
"[Option Start]" border="0"> #include &lt;<a href="../basedefs/unistd.h.html">unistd.h</a>&gt;<br>
<br>
int lchown(const char *</tt><i>path</i><tt>, uid_t</tt> <i>owner</i><tt>, gid_t</tt> <i>group</i><tt>); <img src=
"../images/opt-end.gif" alt="[Option End]" border="0"></tt></code></div>
<tt><br>
</tt></blockquote>
<h4><a name="tag_03_327_03"></a>DESCRIPTION</h4>
<blockquote>
<p>The <i>lchown</i>() function shall be equivalent to <a href="../functions/chown.html"><i>chown</i>()</a>, except in the case
where the named file is a symbolic link. In this case, <i>lchown</i>() shall change the ownership of the symbolic link file itself,
while <a href="../functions/chown.html"><i>chown</i>()</a> changes the ownership of the file or directory to which the symbolic
link refers.</p>
</blockquote>
<h4><a name="tag_03_327_04"></a>RETURN VALUE</h4>
<blockquote>
<p>Upon successful completion, <i>lchown</i>() shall return 0. Otherwise, it shall return -1 and set <i>errno</i> to indicate an
error.</p>
</blockquote>
<h4><a name="tag_03_327_05"></a>ERRORS</h4>
<blockquote>
<p>The <i>lchown</i>() function shall fail if:</p>
<dl compact>
<dt>[EACCES]</dt>
<dd>Search permission is denied on a component of the path prefix of <i>path</i>.</dd>
<dt>[EINVAL]</dt>
<dd>The owner or group ID is not a value supported by the implementation.</dd>
<dt>[ELOOP]</dt>
<dd>A loop exists in symbolic links encountered during resolution of the <i>path</i> argument.</dd>
<dt>[ENAMETOOLONG]</dt>
<dd>
The length of a pathname exceeds {PATH_MAX} or a pathname component is longer than {NAME_MAX}.</dd>
<dt>[ENOENT]</dt>
<dd>A component of <i>path</i> does not name an existing file or <i>path</i> is an empty string.</dd>
<dt>[ENOTDIR]</dt>
<dd>A component of the path prefix of <i>path</i> is not a directory.</dd>
<dt>[EOPNOTSUPP]</dt>
<dd>The <i>path</i> argument names a symbolic link and the implementation does not support setting the owner or group of a symbolic
link.</dd>
<dt>[EPERM]</dt>
<dd>The effective user ID does not match the owner of the file and the process does not have appropriate privileges.</dd>
<dt>[EROFS]</dt>
<dd>The file resides on a read-only file system.</dd>
</dl>
<p>The <i>lchown</i>() function may fail if:</p>
<dl compact>
<dt>[EIO]</dt>
<dd>An I/O error occurred while reading or writing to the file system.</dd>
<dt>[EINTR]</dt>
<dd>A signal was caught during execution of the function.</dd>
<dt>[ELOOP]</dt>
<dd>More than {SYMLOOP_MAX} symbolic links were encountered during resolution of the <i>path</i> argument.</dd>
<dt>[ENAMETOOLONG]</dt>
<dd>
Pathname resolution of a symbolic link produced an intermediate result whose length exceeds {PATH_MAX}.</dd>
</dl>
</blockquote>
<hr>
<div class="box"><em>The following sections are informative.</em></div>
<h4><a name="tag_03_327_06"></a>EXAMPLES</h4>
<blockquote>
<h5><a name="tag_03_327_06_01"></a>Changing the Current Owner of a File</h5>
<p>The following example shows how to change the ownership of the symbolic link named <b>/modules/pass1</b> to the user ID
associated with &quot;jones&quot; and the group ID associated with &quot;cnd&quot;.</p>
<p>The numeric value for the user ID is obtained by using the <a href="../functions/getpwnam.html"><i>getpwnam</i>()</a> function.
The numeric value for the group ID is obtained by using the <a href="../functions/getgrnam.html"><i>getgrnam</i>()</a>
function.</p>
<pre>
<tt>#include &lt;sys/types.h&gt;
#include &lt;unistd.h&gt;
#include &lt;pwd.h&gt;
#include &lt;grp.h&gt;
<br>
struct passwd *pwd;
struct group *grp;
char *path = "/modules/pass1";
...
pwd = getpwnam("jones");
grp = getgrnam("cnd");
lchown(path, pwd-&gt;pw_uid, grp-&gt;gr_gid);
</tt>
</pre>
</blockquote>
<h4><a name="tag_03_327_07"></a>APPLICATION USAGE</h4>
<blockquote>
<p>On implementations which support symbolic links as directory entries rather than files, <i>lchown</i>() may fail.</p>
</blockquote>
<h4><a name="tag_03_327_08"></a>RATIONALE</h4>
<blockquote>
<p>None.</p>
</blockquote>
<h4><a name="tag_03_327_09"></a>FUTURE DIRECTIONS</h4>
<blockquote>
<p>None.</p>
</blockquote>
<h4><a name="tag_03_327_10"></a>SEE ALSO</h4>
<blockquote>
<p><a href="chown.html"><i>chown</i>()</a> , <a href="symlink.html"><i>symlink</i>()</a> , the Base Definitions volume of
IEEE&nbsp;Std&nbsp;1003.1-2001, <a href="../basedefs/unistd.h.html"><i>&lt;unistd.h&gt;</i></a></p>
</blockquote>
<h4><a name="tag_03_327_11"></a>CHANGE HISTORY</h4>
<blockquote>
<p>First released in Issue 4, Version 2.</p>
</blockquote>
<h4><a name="tag_03_327_12"></a>Issue 5</h4>
<blockquote>
<p>Moved from X/OPEN UNIX extension to BASE.</p>
</blockquote>
<h4><a name="tag_03_327_13"></a>Issue 6</h4>
<blockquote>
<p>The wording of the mandatory [ELOOP] error condition is updated, and a second optional [ELOOP] error condition is added.</p>
<p>The Open Group Base Resolution bwg2001-013 is applied, adding wording to the APPLICATION USAGE.</p>
</blockquote>
<div class="box"><em>End of informative text.</em></div>
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