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<div class="subsection" id="Line_002dOriented-Input">
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<p>
Next: <a href="Formatted-Output.html" accesskey="n" rel="next">Formatted Output</a>, Previous: <a href="Simple-Output.html" accesskey="p" rel="prev">Simple Output</a>, Up: <a href="C_002dStyle-I_002fO-Functions.html" accesskey="u" rel="up">C-Style I/O Functions</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html" title="Index" rel="index">Index</a>]</p>
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<span id="Line_002dOriented-Input-1"></span><h4 class="subsection">14.2.3 Line-Oriented Input</h4>
<p>To read from a file it must be opened for reading using <code>fopen</code>.
Then a line can be read from the file using <code>fgetl</code> as the following
code illustrates
</p>
<div class="example">
<pre class="example">fid = fopen ("free.txt");
txt = fgetl (fid)
-| Free Software is needed for Free Science
fclose (fid);
</pre></div>
<p>This of course assumes that the file ‘<samp>free.txt</samp>’ exists and contains
the line ‘<samp>Free Software is needed for Free Science</samp>’.
</p>
<span id="XREFfgetl"></span><dl class="def">
<dt id="index-fgetl"><span class="category">: </span><span><em><var>str</var> =</em> <strong>fgetl</strong> <em>(<var>fid</var>)</em><a href='#index-fgetl' class='copiable-anchor'> ¶</a></span></dt>
<dt id="index-fgetl-1"><span class="category">: </span><span><em><var>str</var> =</em> <strong>fgetl</strong> <em>(<var>fid</var>, <var>len</var>)</em><a href='#index-fgetl-1' class='copiable-anchor'> ¶</a></span></dt>
<dd><p>Read characters from a file, stopping after a newline, or EOF,
or <var>len</var> characters have been read.
</p>
<p>The characters read, excluding the possible trailing newline, are returned
as a string.
</p>
<p>If <var>len</var> is omitted, <code>fgetl</code> reads until the next newline
character.
</p>
<p>If there are no more characters to read, <code>fgetl</code> returns -1.
</p>
<p>To read a line and return the terminating newline,
see <a href="#XREFfgets"><code>fgets</code></a>.
</p>
<p><strong>See also:</strong> <a href="#XREFfgets">fgets</a>, <a href="Formatted-Input.html#XREFfscanf">fscanf</a>, <a href="Binary-I_002fO.html#XREFfread">fread</a>, <a href="Opening-and-Closing-Files.html#XREFfopen">fopen</a>.
</p></dd></dl>
<span id="XREFfgets"></span><dl class="def">
<dt id="index-fgets"><span class="category">: </span><span><em><var>str</var> =</em> <strong>fgets</strong> <em>(<var>fid</var>)</em><a href='#index-fgets' class='copiable-anchor'> ¶</a></span></dt>
<dt id="index-fgets-1"><span class="category">: </span><span><em><var>str</var> =</em> <strong>fgets</strong> <em>(<var>fid</var>, <var>len</var>)</em><a href='#index-fgets-1' class='copiable-anchor'> ¶</a></span></dt>
<dd><p>Read characters from a file, stopping after a newline, or EOF,
or <var>len</var> characters have been read.
</p>
<p>The characters read, including the possible trailing newline, are returned
as a string.
</p>
<p>If <var>len</var> is omitted, <code>fgets</code> reads until the next newline
character.
</p>
<p>If there are no more characters to read, <code>fgets</code> returns -1.
</p>
<p>To read a line and discard the terminating newline,
see <a href="#XREFfgetl"><code>fgetl</code></a>.
</p>
<p><strong>See also:</strong> <a href="Simple-Output.html#XREFfputs">fputs</a>, <a href="#XREFfgetl">fgetl</a>, <a href="Formatted-Input.html#XREFfscanf">fscanf</a>, <a href="Binary-I_002fO.html#XREFfread">fread</a>, <a href="Opening-and-Closing-Files.html#XREFfopen">fopen</a>.
</p></dd></dl>
<span id="XREFfskipl"></span><dl class="def">
<dt id="index-fskipl"><span class="category">: </span><span><em><var>nlines</var> =</em> <strong>fskipl</strong> <em>(<var>fid</var>)</em><a href='#index-fskipl' class='copiable-anchor'> ¶</a></span></dt>
<dt id="index-fskipl-1"><span class="category">: </span><span><em><var>nlines</var> =</em> <strong>fskipl</strong> <em>(<var>fid</var>, <var>count</var>)</em><a href='#index-fskipl-1' class='copiable-anchor'> ¶</a></span></dt>
<dt id="index-fskipl-2"><span class="category">: </span><span><em><var>nlines</var> =</em> <strong>fskipl</strong> <em>(<var>fid</var>, Inf)</em><a href='#index-fskipl-2' class='copiable-anchor'> ¶</a></span></dt>
<dd><p>Read and skip <var>count</var> lines from the file specified by the file
descriptor <var>fid</var>.
</p>
<p><code>fskipl</code> discards characters until an end-of-line is encountered
exactly <var>count</var>-times, or until the end-of-file marker is found.
</p>
<p>If <var>count</var> is omitted, it defaults to 1. <var>count</var> may also be
<code>Inf</code>, in which case lines are skipped until the end of the file.
This form is suitable for counting the number of lines in a file.
</p>
<p>Returns the number of lines skipped (end-of-line sequences encountered).
</p>
<p><strong>See also:</strong> <a href="#XREFfgetl">fgetl</a>, <a href="#XREFfgets">fgets</a>, <a href="Formatted-Input.html#XREFfscanf">fscanf</a>, <a href="Opening-and-Closing-Files.html#XREFfopen">fopen</a>.
</p></dd></dl>
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