NAME¶

strnlen - determine the length of a fixed-size string

LIBRARY¶

Standard C library (libc, -lc)

SYNOPSIS¶

#include <string.h>

size_t strnlen(const char s[.maxlen], size_t maxlen);

strnlen():

    Since glibc 2.10:


        _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 byte ('\0'), but at most maxlen. In doing this, strnlen() looks only at the first maxlen characters in the string pointed to by s and never beyond s[maxlen-1].

RETURN VALUE¶

The strnlen() function returns strlen(s), if that is less than maxlen, or maxlen if there is no null terminating ('\0') among the first maxlen characters pointed to by s.

ATTRIBUTES¶

For an explanation of the terms used in this section, see attributes(7).

STANDARDS¶

POSIX.1-2008.

HISTORY¶

POSIX.1-2008.

SEE ALSO¶

strlen(3)