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# std::strncmp

From cppreference.com
< cpp‎ | string‎ | byte

Defined in header `<cstring>` |  |
int strncmp( const char* lhs, const char* rhs, size_t count ); |  |

Compares at most `count` characters of two null-terminated byte strings. The comparison is done lexicographically.

### [edit] Parameters

lhs, rhs | - | pointers to the null-terminated byte strings to compare
count | - | maximum number of characters to compare

### [edit] Return value

Negative value if `lhs` is less than `rhs`.

​0​ if `lhs` is equal to `rhs`.

Positive value if `lhs` is greater than `rhs`.

### [edit] Example

Run this code

    #include <iostream>
    #include <cstring>

    int main()
    {
        const char world[] = "Hello, world!";
        const char everybody[] = "Hello, everybody!";
        const char somebody[] = "Hello, somebody!";

        // Compares 13 characters of "Hello, world!" and "Hello, everybody!"
        std::cout << std::strncmp(world, everybody, sizeof(world) - 1) << '\n';

        // Compares 13 characters of "Hello, everybody!" and "Hello, world!"
        std::cout << std::strncmp(everybody, world, sizeof(world) - 1) << '\n';

        // Compares 7 characters of "Hello, everybody!" and "Hello, world!"
        std::cout << std::strncmp(everybody, world, sizeof("Hello, ") - 1) << '\n';

        // Compares 5 characters of "Hello, everybody!" and "Hello, somebody!"
        //                                       ^                      ^
        std::cout << std::strncmp(&everybody[12], &somebody[11], sizeof("body!") - 1) << '\n';
    }

Output:

    1
    -1
    0
    0

### [edit] See also

strcmp | compares two strings (function) [edit]
memcmp | compares two buffers (function) [edit]
strcoll | compares two strings in accordance to the current locale (function) [edit]
C documentation for strncmp

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