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<a name="Line_002dOriented-Input"></a>
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<p>
Next: <a href="Formatted-Output.html#Formatted-Output" accesskey="n" rel="next">Formatted Output</a>, Previous: <a href="Simple-Output.html#Simple-Output" accesskey="p" rel="prev">Simple Output</a>, Up: <a href="C_002dStyle-I_002fO-Functions.html#C_002dStyle-I_002fO-Functions" 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#Concept-Index" title="Index" rel="index">Index</a>]</p>
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<a name="Line_002dOriented-Input-1"></a>
<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>
<a name="XREFfgetl"></a><dl>
<dt><a name="index-fgetl"></a>Built-in Function: <em><var>str</var> =</em> <strong>fgetl</strong> <em>(<var>fid</var>)</em></dt>
<dt><a name="index-fgetl-1"></a>Built-in Function: <em><var>str</var> =</em> <strong>fgetl</strong> <em>(<var>fid</var>, <var>len</var>)</em></dt>
<dd><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>
<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 <code>fgets</code>.
</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>
<a name="XREFfgets"></a><dl>
<dt><a name="index-fgets"></a>Built-in Function: <em><var>str</var> =</em> <strong>fgets</strong> <em>(<var>fid</var>)</em></dt>
<dt><a name="index-fgets-1"></a>Built-in Function: <em><var>str</var> =</em> <strong>fgets</strong> <em>(<var>fid</var>, <var>len</var>)</em></dt>
<dd><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>
<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 <code>fgetl</code>.
</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>
<a name="XREFfskipl"></a><dl>
<dt><a name="index-fskipl"></a>Built-in Function: <em><var>nlines</var> =</em> <strong>fskipl</strong> <em>(<var>fid</var>)</em></dt>
<dt><a name="index-fskipl-1"></a>Built-in Function: <em><var>nlines</var> =</em> <strong>fskipl</strong> <em>(<var>fid</var>, <var>count</var>)</em></dt>
<dt><a name="index-fskipl-2"></a>Built-in Function: <em><var>nlines</var> =</em> <strong>fskipl</strong> <em>(<var>fid</var>, Inf)</em></dt>
<dd><p>Read and skip <var>count</var> lines from the file descriptor <var>fid</var>.
<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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Next: <a href="Formatted-Output.html#Formatted-Output" accesskey="n" rel="next">Formatted Output</a>, Previous: <a href="Simple-Output.html#Simple-Output" accesskey="p" rel="prev">Simple Output</a>, Up: <a href="C_002dStyle-I_002fO-Functions.html#C_002dStyle-I_002fO-Functions" 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#Concept-Index" title="Index" rel="index">Index</a>]</p>
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