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 characters 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

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