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  18.           <th colspan="3" align="center">DB_LOGC-&gt;get()</th>
    19. 

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    20. 

  20.         <tr>
    21. 

  21.           <td width="20%" align="left"><a accesskey="p" href="logcclose.html">Prev</a> </td>
    22. 

  22.           <th width="60%" align="center">Chapter 7. 
    23. 

  23.                 The DB_LSN Handle
    24. 

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  31.       <div class="titlepage">
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  32.         <div>
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  33.           <div>
    34. 

  34.             <h2 class="title" style="clear: both"><a id="logcget"></a>DB_LOGC-&gt;get()</h2>
    35. 

  35.           </div>
    36. 

  36.         </div>
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  37.       </div>
    38. 

  38.       <pre class="programlisting">#include &lt;db.h&gt;
    39. 

  39. 

  40. int
    41. 

  41. DB_LOGC-&gt;get(DB_LOGC *logc, DB_LSN *lsn, DBT *data, u_int32_t flags);  </pre>
    42. 

  42.       <p>
    43. 

  43.         The <code class="methodname">DB_LOGC-&gt;get()</code> method returns records from the log.
    44. 

  44.     </p>
    45. 

  45.       <p>
    46. 

  46.          Unless otherwise specified, the <code class="methodname">DB_LOGC-&gt;get()</code> <span>
    47. 

  47.             <span>
    48. 

  48.                   method returns a non-zero error value on failure and 0 on success.
    49. 

  49.             </span>
    50. 

  50.             
    51. 

  51.         </span>
    52. 

  52.     </p>
    53. 

  53.       <div class="sect2" lang="en" xml:lang="en">
    54. 

  54.         <div class="titlepage">
    55. 

  55.           <div>
    56. 

  56.             <div>
    57. 

  57.               <h3 class="title"><a id="id3878931"></a>Parameters</h3>
    58. 

  58.             </div>
    59. 

  59.           </div>
    60. 

  60.         </div>
    61. 

  61.         <div class="sect3" lang="en" xml:lang="en">
    62. 

  62.           <div class="titlepage">
    63. 

  63.             <div>
    64. 

  64.               <div>
    65. 

  65.                 <h4 class="title"><a id="id3878989"></a>lsn</h4>
    66. 

  66.               </div>
    67. 

  67.             </div>
    68. 

  68.           </div>
    69. 

  69.           <p>
    70. 

  70.                           When the <span class="bold"><strong>flag</strong></span> parameter is set to
    71. 

  71.                           DB_CURRENT, DB_FIRST, DB_LAST, DB_NEXT or DB_PREV, the <span class="bold"><strong>lsn</strong></span> parameter is overwritten with the 
    72. 

  72.                           <a class="link" href="lsn.html" title="Chapter 7.  The DB_LSN Handle">DB_LSN</a>  value of the record
    73. 

  73.                           retrieved.  When <span class="bold"><strong>flag</strong></span> is set to
    74. 

  74.                           DB_SET, the <span class="bold"><strong>lsn</strong></span> parameter is the
    75. 

  75.                           <a class="link" href="lsn.html" title="Chapter 7.  The DB_LSN Handle">DB_LSN</a>  value of the
    76. 

  76.                           record to be retrieved.
    77. 

  77.                      </p>
    78. 

  78.         </div>
    79. 

  79.         <div class="sect3" lang="en" xml:lang="en">
    80. 

  80.           <div class="titlepage">
    81. 

  81.             <div>
    82. 

  82.               <div>
    83. 

  83.                 <h4 class="title"><a id="id3879249"></a>data</h4>
    84. 

  84.               </div>
    85. 

  85.             </div>
    86. 

  86.           </div>
    87. 

  87.           <p>
    88. 

  88.                           The data field of the <span class="bold"><strong>data</strong></span> structure
    89. 

  89.                           is set to the record retrieved, and the size field indicates the
    90. 

  90.                           number of bytes in the record.  See 
    91. 

  91.                           <a class="link" href="dbt.html" title="Chapter 4.  The DBT Handle">DBT</a>  for a description of other
    92. 

  92.                           fields in the <span class="bold"><strong>data</strong></span> structure.  The
    93. 

  93.                           <a class="link" href="dbt.html#dbt_DB_DBT_MALLOC">DB_DBT_MALLOC</a>,
    94. 

  94.                           <a class="link" href="dbt.html#dbt_DB_DBT_REALLOC">DB_DBT_REALLOC</a> 
    95. 

  95.                           and <a class="link" href="dbt.html#dbt_DB_DBT_USERMEM">DB_DBT_USERMEM</a> 
    96. 

  96.                           flags may be specified for any 
    97. 

  97.                           <a class="link" href="dbt.html" title="Chapter 4.  The DBT Handle">DBT</a>  used for data retrieval.
    98. 

  98.                      </p>
    99. 

  99.         </div>
    100. 

  100.         <div class="sect3" lang="en" xml:lang="en">
    101. 

  101.           <div class="titlepage">
    102. 

  102.             <div>
    103. 

  103.               <div>
    104. 

  104.                 <h4 class="title"><a id="id3879196"></a>flags</h4>
    105. 

  105.               </div>
    106. 

  106.             </div>
    107. 

  107.           </div>
    108. 

  108.           <p>
    109. 

  109.                           The <span class="bold"><strong>flags</strong></span> parameter must be set to
    110. 

  110.                           one of the following values:
    111. 

  111.                      </p>
    112. 

  112.           <div class="itemizedlist">
    113. 

  113.             <ul type="disc">
    114. 

  114.               <li>
    115. 

  115.                 <p><a id="get_DB_CURRENT"></a>
    116. 

  116.                   <code class="literal">DB_CURRENT</code>
    117. 

  117.             </p>
    118. 

  118.                 <p>
    119. 

  119.                  Return the log record to which the log currently refers.
    120. 

  120.             </p>
    121. 

  121.               </li>
    122. 

  122.               <li>
    123. 

  123.                 <p><a id="get_DB_FIRST"></a>
    124. 

  124.                   <code class="literal">DB_FIRST</code>
    125. 

  125.             </p>
    126. 

  126.                 <p>
    127. 

  127.                  The first record from any of the log files found in the log directory
    128. 

  128.                  is returned in the <span class="bold"><strong>data</strong></span> parameter.
    129. 

  129.                  The <span class="bold"><strong>lsn</strong></span> parameter is overwritten with
    130. 

  130.                  the <a class="link" href="lsn.html" title="Chapter 7.  The DB_LSN Handle">DB_LSN</a>  of the record
    131. 

  131.                  returned.
    132. 

  132.             </p>
    133. 

  133.                 <p>
    134. 

  134.                  The <code class="methodname">DB_LOGC-&gt;get()</code> method will return <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_NOTFOUND" class="olink">DB_NOTFOUND</a> if
    135. 

  135.                  DB_FIRST is set and the log is empty.
    136. 

  136.             </p>
    137. 

  137.               </li>
    138. 

  138.               <li>
    139. 

  139.                 <p><a id="get_DB_LAST"></a>
    140. 

  140.                  <code class="literal">DB_LAST</code>
    141. 

  141.             </p>
    142. 

  142.                 <p>
    143. 

  143.                  The last record in the log is returned in the <span class="bold"><strong>data</strong></span> parameter. The <span class="bold"><strong>lsn</strong></span> parameter is overwritten with the 
    144. 

  144.                  <a class="link" href="lsn.html" title="Chapter 7.  The DB_LSN Handle">DB_LSN</a>  of the record returned.
    145. 

  145.             </p>
    146. 

  146.                 <p>
    147. 

  147.                  The <code class="methodname">DB_LOGC-&gt;get()</code> method will return <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_NOTFOUND" class="olink">DB_NOTFOUND</a> if
    148. 

  148.                  DB_LAST is set and the log is empty.
    149. 

  149.             </p>
    150. 

  150.               </li>
    151. 

  151.               <li>
    152. 

  152.                 <p><a id="get_DB_NEXT"></a>
    153. 

  153.                  <code class="literal">DB_NEXT</code>
    154. 

  154.             </p>
    155. 

  155.                 <p>
    156. 

  156.                  The current log position is advanced to the next record in the log,
    157. 

  157.                  and that record is returned in the <span class="bold"><strong>data</strong></span> parameter.  The <span class="bold"><strong>lsn</strong></span> parameter is overwritten with the 
    158. 

  158.                  <a class="link" href="lsn.html" title="Chapter 7.  The DB_LSN Handle">DB_LSN</a>  of the record returned.
    159. 

  159.             </p>
    160. 

  160.                 <p>
    161. 

  161.                  If the cursor has not been initialized via DB_FIRST, DB_LAST, DB_SET,
    162. 

  162.                  DB_NEXT, or DB_PREV, <code class="methodname">DB_LOGC-&gt;get()</code> will return the first record in
    163. 

  163.                  the log.
    164. 

  164.             </p>
    165. 

  165.                 <p>
    166. 

  166.                  The <code class="methodname">DB_LOGC-&gt;get()</code> method will return <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_NOTFOUND" class="olink">DB_NOTFOUND</a> if
    167. 

  167.                  DB_NEXT is set and the last log record has already been returned or
    168. 

  168.                  the log is empty.
    169. 

  169.             </p>
    170. 

  170.               </li>
    171. 

  171.               <li>
    172. 

  172.                 <p><a id="get_DB_PREV"></a>
    173. 

  173.                  <code class="literal">DB_PREV</code>
    174. 

  174.             </p>
    175. 

  175.                 <p>
    176. 

  176.                  The current log position is advanced to the previous record in the
    177. 

  177.                  log, and that record is returned in the <span class="bold"><strong>data</strong></span> parameter.  The <span class="bold"><strong>lsn</strong></span> parameter is overwritten with the 
    178. 

  178.                  <a class="link" href="lsn.html" title="Chapter 7.  The DB_LSN Handle">DB_LSN</a>  of the record returned.
    179. 

  179.             </p>
    180. 

  180.                 <p>
    181. 

  181.                  If the cursor has not been initialized via DB_FIRST, DB_LAST, DB_SET,
    182. 

  182.                  DB_NEXT, or DB_PREV, <code class="methodname">DB_LOGC-&gt;get()</code> will return the last record in
    183. 

  183.                  the log.
    184. 

  184.             </p>
    185. 

  185.                 <p>
    186. 

  186.                  The <code class="methodname">DB_LOGC-&gt;get()</code> method will return <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_NOTFOUND" class="olink">DB_NOTFOUND</a> if
    187. 

  187.                  DB_PREV is set and the first log record has already been returned or
    188. 

  188.                  the log is empty.
    189. 

  189.             </p>
    190. 

  190.               </li>
    191. 

  191.               <li>
    192. 

  192.                 <p><a id="get_DB_SET"></a>
    193. 

  193.                  <code class="literal">DB_SET</code>
    194. 

  194.             </p>
    195. 

  195.                 <p>
    196. 

  196.                  Retrieve the record specified by the <span class="bold"><strong>lsn</strong></span> parameter.
    197. 

  197.             </p>
    198. 

  198.               </li>
    199. 

  199.             </ul>
    200. 

  200.           </div>
    201. 

  201.         </div>
    202. 

  202.       </div>
    203. 

  203.       <div class="sect2" lang="en" xml:lang="en">
    204. 

  204.         <div class="titlepage">
    205. 

  205.           <div>
    206. 

  206.             <div>
    207. 

  207.               <h3 class="title"><a id="id3879473"></a>Errors</h3>
    208. 

  208.             </div>
    209. 

  209.           </div>
    210. 

  210.         </div>
    211. 

  211.         <p>
    212. 

  212.                          The <code class="methodname">DB_LOGC-&gt;get()</code> <span>
    213. 

  213.             <span>
    214. 

  214.                  method may fail and return one of the following non-zero errors:
    215. 

  215.             </span>
    216. 

  216.             
    217. 

  217.         </span>
    218. 

  218.                     </p>
    219. 

  219.         <div class="sect3" lang="en" xml:lang="en">
    220. 

  220.           <div class="titlepage">
    221. 

  221.             <div>
    222. 

  222.               <div>
    223. 

  223.                 <h4 class="title"><a id="id3879278"></a>EINVAL</h4>
    224. 

  224.               </div>
    225. 

  225.             </div>
    226. 

  226.           </div>
    227. 

  227.           <p>
    228. 

  228.                               If the DB_CURRENT flag was set and the log cursor has not yet been
    229. 

  229.                               initialized; the DB_CURRENT, DB_NEXT, or DB_PREV flags were set and
    230. 

  230.                               the log was opened with the DB_THREAD flag set; the DB_SET flag was
    231. 

  231.                               set and the specified log sequence number does not appear in the log;
    232. 

  232.                               or if an invalid flag value or parameter was specified.
    233. 

  233.                          </p>
    234. 

  234.         </div>
    235. 

  235.       </div>
    236. 

  236.       <div class="sect2" lang="en" xml:lang="en">
    237. 

  237.         <div class="titlepage">
    238. 

  238.           <div>
    239. 

  239.             <div>
    240. 

  240.               <h3 class="title"><a id="id3878979"></a>Class</h3>
    241. 

  241.             </div>
    242. 

  242.           </div>
    243. 

  243.         </div>
    244. 

  244.         <p>
    245. 

  245.                     <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>, 
    246. 

  246.                     <a class="link" href="logc.html" title="The DB_LOGC Handle">DB_LOGC</a>, 
    247. 

  247.                     <a class="link" href="lsn.html" title="Chapter 7.  The DB_LSN Handle">DB_LSN</a> 
    248. 

  248.             </p>
    249. 

  249.       </div>
    250. 

  250.       <div class="sect2" lang="en" xml:lang="en">
    251. 

  251.         <div class="titlepage">
    252. 

  252.           <div>
    253. 

  253.             <div>
    254. 

  254.               <h3 class="title"><a id="id3879259"></a>See Also</h3>
    255. 

  255.             </div>
    256. 

  256.           </div>
    257. 

  257.         </div>
    258. 

  258.         <p>
    259. 

  259.                      <a class="xref" href="lsn.html#loglist" title="Logging Subsystem and Related Methods">Logging Subsystem and Related Methods</a> 
    260. 

  260.                 </p>
    261. 

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    262. 

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    264. 

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    268. 

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    269. 

  269.             <a accesskey="u" href="lsn.html">Up</a>
    270. 

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