1<html lang="en"> 2<head> 3<title>getchar - Untitled</title> 4<meta http-equiv="Content-Type" content="text/html"> 5<meta name="description" content="Untitled"> 6<meta name="generator" content="makeinfo 4.13"> 7<link title="Top" rel="start" href="index.html#Top"> 8<link rel="up" href="Stdio.html#Stdio" title="Stdio"> 9<link rel="prev" href="getc_005funlocked.html#getc_005funlocked" title="getc_unlocked"> 10<link rel="next" href="getchar_005funlocked.html#getchar_005funlocked" title="getchar_unlocked"> 11<link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage"> 12<meta http-equiv="Content-Style-Type" content="text/css"> 13<style type="text/css"><!-- 14 pre.display { font-family:inherit } 15 pre.format { font-family:inherit } 16 pre.smalldisplay { font-family:inherit; font-size:smaller } 17 pre.smallformat { font-family:inherit; font-size:smaller } 18 pre.smallexample { font-size:smaller } 19 pre.smalllisp { font-size:smaller } 20 span.sc { font-variant:small-caps } 21 span.roman { font-family:serif; font-weight:normal; } 22 span.sansserif { font-family:sans-serif; font-weight:normal; } 23--></style> 24<link rel="stylesheet" type="text/css" href="../cs.css"> 25</head> 26<body> 27<div class="node"> 28<a name="getchar"></a> 29<p> 30Next: <a rel="next" accesskey="n" href="getchar_005funlocked.html#getchar_005funlocked">getchar_unlocked</a>, 31Previous: <a rel="previous" accesskey="p" href="getc_005funlocked.html#getc_005funlocked">getc_unlocked</a>, 32Up: <a rel="up" accesskey="u" href="Stdio.html#Stdio">Stdio</a> 33<hr> 34</div> 35 36<h3 class="section">4.34 <code>getchar</code>—read a character (macro)</h3> 37 38<p><a name="index-getchar-218"></a><a name="index-g_t_005fgetchar_005fr-219"></a><strong>Synopsis</strong> 39<pre class="example"> #include <stdio.h> 40 int getchar(void); 41 42 int _getchar_r(struct _reent *<var>reent</var>); 43 44</pre> 45 <p><strong>Description</strong><br> 46<code>getchar</code> is a macro, defined in <code>stdio.h</code>. You can use <code>getchar</code> 47to get the next single character from the standard input stream. 48As a side effect, <code>getchar</code> advances the standard input's 49current position indicator. 50 51 <p>The alternate function <code>_getchar_r</code> is a reentrant version. The 52extra argument <var>reent</var> is a pointer to a reentrancy structure. 53 54 <p><br> 55<strong>Returns</strong><br> 56The next character (read as an <code>unsigned char</code>, and cast to 57<code>int</code>), unless there is no more data, or the host system reports a 58read error; in either of these situations, <code>getchar</code> returns <code>EOF</code>. 59 60 <p>You can distinguish the two situations that cause an <code>EOF</code> result by 61using `<code>ferror(stdin)</code>' and `<code>feof(stdin)</code>'. 62 63 <p><br> 64<strong>Portability</strong><br> 65ANSI C requires <code>getchar</code>; it suggests, but does not require, that 66<code>getchar</code> be implemented as a macro. 67 68 <p>Supporting OS subroutines required: <code>close</code>, <code>fstat</code>, <code>isatty</code>, 69<code>lseek</code>, <code>read</code>, <code>sbrk</code>, <code>write</code>. 70 71 <p><br> 72 73 </body></html> 74 75