strcmp C Library Function

The function int strcmp(const char *str1, const char *str2); compares string pointed by str1 with string pointed by str2. This function compares both string character by character. It will continue comparison until the characters mismatch or until a terminating null-character is reached.

Function prototype of strcmp

int strcmp(const char *str1, const char *str2);
  • str1 : A pointer to a C string to be compared.
  • str2 : A pointer to a C string to be compared.

Return value of strcmp

Return Value Description
Positive (>0) str2 is less than str1
Zero (==0) str1 is equal to str2
Negative (<0) str1 is less than str2

C program using strcmp function

The following program shows the use of strcmp function to compare two strings.

strcmp C Library Function

#include <stdio.h>
#include <string.h>
#include <conio.h>
int main()
   char firstString[100], secondString[100];
   int response;
   printf("Enter first string\n");
   scanf("%s", &firstString);
   printf("Enter second string\n");
   scanf("%s", &secondString);
   response = strcmp(firstString, secondString, 5);
   if(response > 0){
      printf("second String is less than first String");
   else if(response < 0) {
      printf("first String is less than second String");
   else {
      printf("first String is equal to second String");


Enter first string
Enter second string
second String is less than first String
Enter first string
Enter second string
first String is equal to second String