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  16. <title>lseek (Debugging with GDB)</title>
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  61. </div>
  62. <hr>
  63. <a name="lseek-1"></a>
  64. <h4 class="unnumberedsubsubsec">lseek</h4>
  65. <a name="index-lseek_002c-file_002di_002fo-system-call"></a>
  66. <dl compact="compact">
  67. <dt>Synopsis:</dt>
  68. <dd><div class="smallexample">
  69. <pre class="smallexample">long lseek (int fd, long offset, int flag);
  70. </pre></div>
  71. </dd>
  72. <dt>Request:</dt>
  73. <dd><p>&lsquo;<samp>Flseek,<var>fd</var>,<var>offset</var>,<var>flag</var></samp>&rsquo;
  74. </p>
  75. <p><var>flag</var> is one of:
  76. </p>
  77. <dl compact="compact">
  78. <dt><code>SEEK_SET</code></dt>
  79. <dd><p>The offset is set to <var>offset</var> bytes.
  80. </p>
  81. </dd>
  82. <dt><code>SEEK_CUR</code></dt>
  83. <dd><p>The offset is set to its current location plus <var>offset</var>
  84. bytes.
  85. </p>
  86. </dd>
  87. <dt><code>SEEK_END</code></dt>
  88. <dd><p>The offset is set to the size of the file plus <var>offset</var>
  89. bytes.
  90. </p></dd>
  91. </dl>
  92. </dd>
  93. <dt>Return value:</dt>
  94. <dd><p>On success, the resulting unsigned offset in bytes from
  95. the beginning of the file is returned. Otherwise, a
  96. value of -1 is returned.
  97. </p>
  98. </dd>
  99. <dt>Errors:</dt>
  100. <dd>
  101. <dl compact="compact">
  102. <dt><code>EBADF</code></dt>
  103. <dd><p><var>fd</var> is not a valid open file descriptor.
  104. </p>
  105. </dd>
  106. <dt><code>ESPIPE</code></dt>
  107. <dd><p><var>fd</var> is associated with the <small>GDB</small> console.
  108. </p>
  109. </dd>
  110. <dt><code>EINVAL</code></dt>
  111. <dd><p><var>flag</var> is not a proper value.
  112. </p>
  113. </dd>
  114. <dt><code>EINTR</code></dt>
  115. <dd><p>The call was interrupted by the user.
  116. </p></dd>
  117. </dl>
  118. </dd>
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