1<html lang="en"> 2<head> 3<title>strlen - 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="Strings.html#Strings" title="Strings"> 9<link rel="prev" href="strerror_005fr.html#strerror_005fr" title="strerror_r"> 10<link rel="next" href="strlwr.html#strlwr" title="strlwr"> 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="strlen"></a> 29<p> 30Next: <a rel="next" accesskey="n" href="strlwr.html#strlwr">strlwr</a>, 31Previous: <a rel="previous" accesskey="p" href="strerror_005fr.html#strerror_005fr">strerror_r</a>, 32Up: <a rel="up" accesskey="u" href="Strings.html#Strings">Strings</a> 33<hr> 34</div> 35 36<h3 class="section">5.26 <code>strlen</code>—character string length</h3> 37 38<p><a name="index-strlen-394"></a><strong>Synopsis</strong> 39<pre class="example"> #include <string.h> 40 size_t strlen(const char *<var>str</var>); 41 42</pre> 43 <p><strong>Description</strong><br> 44The <code>strlen</code> function works out the length of the string 45starting at <code>*</code><var>str</var> by counting chararacters until it 46reaches a <code>NULL</code> character. 47 48 <p><br> 49<strong>Returns</strong><br> 50<code>strlen</code> returns the character count. 51 52 <p><br> 53<strong>Portability</strong><br> 54<code>strlen</code> is ANSI C. 55 56 <p><code>strlen</code> requires no supporting OS subroutines. 57 58 <p><br> 59 60 </body></html> 61 62