strnlen

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:
               _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.

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).

       ┌──────────┬───────────────┬─────────┐
       │Interface Attribute     Value   │
       ├──────────┼───────────────┼─────────┤
       │strnlen() │ Thread safety │ MT-Safe │
       └──────────┴───────────────┴─────────┘
CONFORMING TO
       POSIX.1-2008.

SEE ALSO
       strlen(3)

COLOPHON
       This page is part of release 5.06 of the Linux man-pages project.  A
       description of the project, information about reporting bugs, and the
       latest version of this page, can be found at
       https://www.kernel.org/doc/man-pages/.



GNU                               2019-03-06                        STRNLEN(3)