105 lines
		
	
	
		
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			105 lines
		
	
	
		
			3.5 KiB
		
	
	
	
		
			HTML
		
	
	
	
	
	
| <!--
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| Copyright (c) 2000, 2001, 2002, 2003, 2004, 2005, 2008, 2009, 2013
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| 	The President and Fellows of Harvard College.
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| <html>
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| <head>
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| <title>readlink</title>
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| <link rel="stylesheet" type="text/css" media="all" href="../man.css">
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| </head>
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| <body bgcolor=#ffffff>
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| <h2 align=center>readlink</h2>
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| <h4 align=center>OS/161 Reference Manual</h4>
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| 
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| <h3>Name</h3>
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| <p>
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| readlink - fetch symbolic link contents
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| </p>
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| 
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| <h3>Library</h3>
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| <p>
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| Standard C Library (libc, -lc)
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| </p>
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| 
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| <h3>Synopsis</h3>
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| <p>
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| <tt>#include <unistd.h></tt><br>
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| <br>
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| <tt>int</tt><br>
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| <tt>readlink(const char *</tt><em>path</em><tt>, char *</tt><em>buf</em><tt>,
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| size_t </tt><em>len</em><tt>);</tt>
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| </p>
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| 
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| <h3>Description</h3>
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| <p>
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| <tt>readlink</tt> retrieves the contents of the symbolic link named by
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| <em>path</em> and places them in the buffer <em>buf</em>. At most
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| <em>len</em> bytes are written.
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| </p>
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| 
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| <p>
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| <tt>readlink</tt> does not include a null terminator in <em>buf</em>.
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| </p>
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| 
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| <p>
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| The call (like all system calls) should be atomic.
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| Note that the kernel is not obliged to (and generally cannot) make the
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| read atomic with respect to other threads in the same process
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| accessing the buffer during the operation.
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| </p>
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| 
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| <h3>Return Values</h3>
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| <p>
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| <tt>readlink</tt> returns the number of characters transferred. If an
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| error occurs, -1 is returned, and <A HREF=errno.html>errno</A> is set
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| according to the error encountered.
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| </p>
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| 
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| <h3>Errors</h3>
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| <p>
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| The following error codes should be returned under the conditions
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| given. Other error codes may be returned for other cases not
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| mentioned here.
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| 
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| <table width=90%>
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| <tr><td width=5% rowspan=6> </td>
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|     <td width=10% valign=top>ENODEV</td>
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| 				<td>The device prefix of <em>filename</em> did
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| 				not exist.</td></tr>
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| <tr><td valign=top>ENOTDIR</td>	<td>A non-final component of <em>path</em>
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| 				was not a directory.</td></tr>
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| <tr><td valign=top>ENOENT</td>	<td>The named file does not exist.</td></tr>
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| <tr><td valign=top>EINVAL</td>	<td>The named file is not a symlink.</td></tr>
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| <tr><td valign=top>EIO</td>	<td>A hard I/O error occurred.</td></tr>
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| <tr><td valign=top>EFAULT</td>	<td><em>buf</em> or <em>path</em> points to an
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| 				invalid address.</td></tr>
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| </table>
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| </p>
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| 
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| </body>
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| </html>
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