strcmp

 

C

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Strings library

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Null-terminated byte strings

Functions
Character manipulation
isalnum isalpha islower isupper isdigit isxdigit isblank (C99)	iscntrl isgraph isspace isprint ispunct tolower toupper
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atof atoiatolatoll strtolstrtoll	strtoulstrtoull strtofstrtodstrtold
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strlen strcmp strncmp strcoll strchr strrchr	strspn strcspn strpbrk strstr strtok
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memchr
memcmp
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Defined in header <string.h>
int strcmp( const char *lhs, const char *rhs );

Compares two null-terminated byte strings. The comparison is done lexicographically.

Parameters

lhs, rhs

-

pointers to the null-terminated byte strings to compare

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.

Example

Run this code

#include <string.h>
#include <stdio.h>
 
int main(void) 
{
    const char* string = "Hello World!";
 
    //Matches
    int a = strcmp(string, "Hello World!");
    if (a == 0) {
        printf("Strings are matching.\n");
    }
 
    //Greater than
    int b = strcmp(string, "Hello");
    if (b >= 1) {
        printf("Left hand side is bigger than right hand side.\n");
    }
 
    //less than
    int c = strcmp(string, "Hello there world!");
    if (c <= -1) {
        printf("Left hand side is smaller than right hand side.\n");
    }
}

Output:

Strings are matching.
Left hand side is bigger than right hand side.
Left hand side is smaller than right hand side.

See also

strncmp	compares a certain amount of characters of two strings (function)
memcmp	compares two buffers (function)
strcoll	compares two strings in accordance to the current locale (function)
C++ documentation for strcmp