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<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
<pre class="example"> fid = fopen ("free.txt");
txt = fgetl (fid)
-| Free Software is needed for Free Science
fclose (fid);
</pre>
<p class="noindent">This of course assumes that the file ‘<samp><span class="samp">free.txt</span></samp>’ exists and contains
the line ‘<samp><span class="samp">Free Software is needed for Free Science</span></samp>’.
<!-- fgetl src/file-io.cc -->
<p><a name="doc_002dfgetl"></a>
<div class="defun">
— Built-in Function: <b>fgetl</b> (<var>fid, len</var>)<var><a name="index-fgetl-984"></a></var><br>
<blockquote><p>Read characters from a file, stopping after a newline, or EOF,
or <var>len</var> characters have been read. The characters read, excluding
the possible trailing newline, are returned as a string.
<p>If <var>len</var> is omitted, <code>fgetl</code> reads until the next newline
character.
<p>If there are no more characters to read, <code>fgetl</code> returns −1.
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<p class="noindent"><strong>See also:</strong> <a href="doc_002dfread.html#doc_002dfread">fread</a>, <a href="doc_002dfscanf.html#doc_002dfscanf">fscanf</a>.
</p></blockquote></div>
<!-- fgets src/file-io.cc -->
<p><a name="doc_002dfgets"></a>
<div class="defun">
— Built-in Function: <b>fgets</b> (<var>fid</var>)<var><a name="index-fgets-985"></a></var><br>
— Built-in Function: <b>fgets</b> (<var>fid, len</var>)<var><a name="index-fgets-986"></a></var><br>
<blockquote><p>Read characters from a file, stopping after a newline, or EOF,
or <var>len</var> characters have been read. The characters read, including
the possible trailing newline, are returned as a string.
<p>If <var>len</var> is omitted, <code>fgets</code> reads until the next newline
character.
<p>If there are no more characters to read, <code>fgets</code> returns −1.
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<p class="noindent"><strong>See also:</strong> <a href="doc_002dfputs.html#doc_002dfputs">fputs</a>, <a href="doc_002dfopen.html#doc_002dfopen">fopen</a>, <a href="doc_002dfread.html#doc_002dfread">fread</a>, <a href="doc_002dfscanf.html#doc_002dfscanf">fscanf</a>.
</p></blockquote></div>
<!-- fskipl src/file-io.cc -->
<p><a name="doc_002dfskipl"></a>
<div class="defun">
— Built-in Function: <b>fskipl</b> (<var>fid, count</var>)<var><a name="index-fskipl-987"></a></var><br>
<blockquote><p>Skip a given number of lines, i.e., discards characters until an end-of-line
is met exactly <var>count</var>-times, or end-of-file occurs.
Returns the number of lines skipped (end-of-line sequences encountered).
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 to the end of file.
This form is suitable for counting lines in a file.
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<p class="noindent"><strong>See also:</strong> <a href="doc_002dfgetl.html#doc_002dfgetl">fgetl</a>, <a href="doc_002dfgets.html#doc_002dfgets">fgets</a>.
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