axf-os161 / man / syscall / symlink.html
symlink.html
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<html>
<head>
<title>symlink</title>
<body bgcolor=#ffffff>
<h2 align=center>symlink</h2>
<h4 align=center>OS/161 Reference Manual</h4>

<h3>Name</h3>
<p>
symlink - create symbolic link
</p>

<h3>Library</h3>
<p>
Standard C Library (libc, -lc)
</p>

<h3>Synopsis</h3>
<p>
<tt>#include &lt;unistd.h&gt;</tt><br>
<br>
<tt>int</tt><br>
<tt>symlink(const char *</tt><em>oldname</em><tt>,
const char *</tt><em>linkname</em><tt>);</tt>
</p>

<h3>Description</h3>
<p>
<tt>symlink</tt> creates a symbolic link. The symlink itself is named
<em>linkname</em>, and it points to <em>oldname</em>.
</p>

<p>
<em>oldname</em> need not exist or be on the same filesystem.
</p>

<p>
The call (like all system calls) must be atomic; that is, the symlink
should either be created or not created, and no other process should
see an intermediate state (such as, for example, a blank symlink whose
name hasn't been written out yet...) For recoverable file systems,
this includes after crash recovery.
</p>

<h3>Return Values</h3>
<p>
On success, <tt>symlink</tt> returns 0. On error, -1 is returned, and
<A HREF=errno.html>errno</A> is set according to the error
encountered.
</p>

<h3>Errors</h3>
<p>
The following error codes should be returned under the conditions
given. Other error codes may be returned for other cases not
mentioned here.

<table width=90%>
<tr><td width=5% rowspan=7>&nbsp;</td>
    <td width=10% valign=top>ENODEV</td>
				<td>The device prefix of <em>filename</em> did
				not exist.</td></tr>
<tr><td valign=top>ENOTDIR</td>	<td>A non-final component of <em>linkname</em>
				was not a directory.</td></tr>
<tr><td valign=top>ENOENT</td>	<td>A non-final component of <em>linkname</em>
				did not exist.</td></tr>
<tr><td valign=top>EEXIST</td>	<td><em>linkname</em> already exists.</td></tr>
<tr><td valign=top>ENOSPC</td>	<td>The filesystem that was to hold the link
				is full.</td></tr>
<tr><td valign=top>EIO</td>	<td>A hard I/O error occurred.</td></tr>
<tr><td valign=top>EFAULT</td>	<td><em>linkname</em> or <em>oldname</em> was
				an invalid pointer.</td></tr>
</table>
</p>

</body>
</html>