NAME

       strlen - calculate the length of a string

LIBRARY

       Standard C library (libc, -lc)

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 bytes 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 │
       └───────────────────────────────────────────────────────────────┴───────────────┴─────────┘

STANDARDS

       C11, POSIX.1-2008.

HISTORY

       POSIX.1-2001, C89, SVr4, 4.3BSD.

NOTES

       In cases where the input buffer may not contain a terminating null byte, strnlen(3) should
       be used instead.

SEE ALSO

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