The strcmp() compares two strings character by character. If the strings are equal, the function returns 0.
C strcmp() Prototype
The function prototype of strcmp() is:
int strcmp (const char* str1, const char* str2);
strcmp() Parameters
The function takes two parameters:
- str1 - a string
- str2 - a string
Return Value from strcmp()
| Return Value | Remarks |
|---|---|
| 0 | if strings are equal |
| >0 | if the first non-matching character in str1 is greater (in ASCII) than that of str2. |
| <0 | if the first non-matching character in str1 is lower (in ASCII) than that of str2. |
The strcmp() function is defined in the string.h header file.
Example: C strcmp() function
#include <stdio.h>
#include <string.h>
int main() {
char str1[] = "abcd", str2[] = "abCd", str3[] = "abcd";
int result;
// comparing strings str1 and str2
result = strcmp(str1, str2);
printf("strcmp(str1, str2) = %d\n", result);
// comparing strings str1 and str3
result = strcmp(str1, str3);
printf("strcmp(str1, str3) = %d\n", result);
return 0;
}
Output
strcmp(str1, str2) = 32 strcmp(str1, str3) = 0
In the program,
- strings
str1andstr2are not equal. Hence, the result is a non-zero integer. - strings
str1andstr3are equal. Hence, the result is 0.