NAME
strlen - string length
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').
It is equivalent to
strnul(s) - s
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.