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Top Forums Programming pointer arithmetic vs. strlen() & strnlen()? Post 302280373 by jjinno on Monday 26th of January 2009 05:20:06 PM
Old 01-26-2009
pointer arithmetic vs. strlen() & strnlen()?

I have been getting some flack recently for my use of strlen() and strnlen(). Honestly I have always just taken their functionality for granted as being the easiest way of getting the length of a string. Is it really so much better to do pointer arithmetic? What am I gaining besides more thought-process for me to worry about?
 

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STRNLEN(3)						     Linux Programmer's Manual							STRNLEN(3)

NAME
strnlen - determine the length of a fixed-size string SYNOPSIS
#include <string.h> size_t strnlen(const char *s, size_t maxlen); Feature Test Macro Requirements for glibc (see feature_test_macros(7)): strnlen(): Since glibc 2.10: _XOPEN_SOURCE >= 700 || _POSIX_C_SOURCE >= 200809L Before glibc 2.10: _GNU_SOURCE DESCRIPTION
The strnlen() function returns the number of bytes in the string pointed to by s, excluding the terminating null bye (''), but at most maxlen. In doing this, strnlen() looks only at the first maxlen bytes at s and never beyond s+maxlen. RETURN VALUE
The strnlen() function returns strlen(s), if that is less than maxlen, or maxlen if there is no null byte ('') among the first maxlen bytes pointed to by s. CONFORMING TO
POSIX.1-2008. SEE ALSO
strlen(3) COLOPHON
This page is part of release 3.44 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/. GNU
2012-05-10 STRNLEN(3)
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