strlen(3)


NAME

   strlen - calculate the length of a string

SYNOPSIS

   #include <string.h>

   size_t strlen(const char *s);

DESCRIPTION

   The strlen() function calculates the length of the string pointed to by
   s, excluding the terminating null byte ('\0').

RETURN VALUE

   The strlen() function returns the number of characters  in  the  string
   pointed to by s.

ATTRIBUTES

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

   
   Interface  Attribute      Value   
   
   strlen()   Thread safety  MT-Safe 
   

CONFORMING TO

   POSIX.1-2001, POSIX.1-2008, C89, C99, C11, SVr4, 4.3BSD.

SEE ALSO

   string(3), strnlen(3), wcslen(3), wcsnlen(3)

COLOPHON

   This page is part of release 4.09 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/.





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