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13<b>db_env_set_func_seek</b>
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21<b><pre>
22#include &lt;db.h&gt;
23<p>
24int
25db_env_set_func_seek(int (*func_seek)(int fd, off_t offset, int whence));
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28<b>Description: db_env_set_func_seek</b>
29<p>The Berkeley DB library requires the ability to specify that a subsequent read
30from or write to a file will occur at a specific location in that file.</p>
31<p>The db_env_set_func_seek method configures all operations performed by a process and
32all of its threads of control, not operations confined to a single
33database environment.</p>
34<p>Although the db_env_set_func_seek method may be called at any time during the life of
35the application, it should normally be called before making calls to the
36<a href="../api_c/env_class.html">db_env_create</a> or <a href="../api_c/db_class.html">db_create</a> methods.</p>
37<p>The db_env_set_func_seek method
38returns a non-zero error value on failure
39and 0 on success.
40</p>
41<b>Parameters</b> <br>
42 <b>func_seek</b><ul compact><li>The <b>func_seek</b> parameter is the function which seeks to a specific
43location in a file.
44<p>The <b>fd</b> parameter is an open file descriptor on the file.</p>
45<p>The <b>seek</b> function must cause a subsequent read from or write to
46the file to occur at the byte offset specified by the <b>offset</b>
47parameter.</p>
48<p>The <b>whence</b> parameter specifies where in the file the byte offset
49is relative to, as described by the IEEE/ANSI Std 1003.1 (POSIX) <b>lseek</b> system
50call.</p>
51<p>The <b>func_seek</b> function must return the value of <b>errno</b> on
52failure and 0 on success.</p></ul>
53<br>
54<br><b>See Also</b>
55<a href="../ref/program/runtime.html">Run-time configuration</a>
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