strncmp function

C

Function

Reference manual

@see man strncmp

The strncmp function is used to compare a specified number of characters in two null-terminated strings. It compares the characters in the two strings up to a specified maximum length and returns an integer value indicating the result of the comparison.

Syntax

int strncmp(const char *str1, const char *str2, size_t n);

Parameters

• str1: A pointer to the first null-terminated string to be compared.
• str2: A pointer to the second null-terminated string to be compared.
• n: The maximum number of characters to compare.

Return value

Returns a value less than, equal to, or greater than zero, depending on whether str1 is lexicographically less than, equal to, or greater than str2, respectively.

Example

In the following example we use the strncmp function to compare the strings “apple” and “appetite” adn based on the return value output which is lexicographically greater or wether they are equal.

#include <stdio.h>
#include <string.h>

int main(void) {
    const char *str1 = "apple";
    const char *str2 = "appetite";
    int result = strncmp(str1, str2, 3);
    
    if (result < 0)
        printf("str1 is lexicographically less than str2.\n");
    else if (result == 0)
        printf("str1 is equal to str2.\n");
    else
        printf("str1 is lexicographically greater than str2.\n");
    return (0);
}