< cpp‎ | string‎ | byte
Defined in header <cstring>
std::size_t strlen( const char* str );

Returns the length of the given null-terminated byte string, that is, the number of characters that precede the terminating null character.


[edit] Parameters

str - pointer to the null-terminated byte string to be examined

[edit] Return value

The length of the null-terminated string str.

[edit] Example

#include <cstring>
#include <iostream>
int main()
   const char str[] = "How many characters does this string contain?";
   std::cout << "without null character: " << std::strlen(str) << '\n'
             << "with null character: " << sizeof(str) << '\n';


without null character: 45
with null character: 46

[edit] See also

C documentation for strlen