NAME

strcmp - compare two strings

strcmp, strncmp - compare two strings

SYNOPSIS

#include <cs50.h>
#include <string.h>

int strcmp(string s1, string s2);

#include <string.h>

int strcmp(const char *s1, const char *s2);

int strncmp(const char *s1, const char *s2, size_t n);

DESCRIPTION

This function compares two strings case-sensitively.

The strcmp() function compares the two strings s1 and s2. The locale is not taken into account (for a locale-aware comparison, see strcoll(3)). It returns an integer less than, equal to, or greater than zero if s1 is found, respectively, to be less than, to match, or be greater than s2.

The strncmp() function is similar, except it compares only the first (at most) n bytes of s1 and s2.

RETURN VALUE

This function returns

an int less than 0 if s1 comes before s2,
0 if s1 is the same as s2,
an int greater than 0 if s1 comes after s2.

The strings are compared using “ASCIIbetical” order, based on the ASCII values of their characters. For instance, "AAA" would come before "BBB", and "AAA" would also come before "aaa".

The strcmp() and strncmp() functions return an integer less than, equal to, or greater than zero if s1 (or the first n bytes thereof) is found, respectively, to be less than, to match, or be greater than s2.

EXAMPLE

#include <cs50.h>
#include <stdio.h>
#include <string.h>

int main(void)
{
    string s1 = get_string("s1: ");
    string s2 = get_string("s2: ");
    if (strcmp(s1, s2) == 0)
    {
        printf("Those are the same.\n");
    }
    else
    {
        printf("Those are different.\n");
    }
}

ATTRIBUTES

For an explanation of the terms used in this section, see attributes(7).

Interface	Attribute	Value
strcmp(), strncmp()	Thread safety	MT-Safe

CONFORMING TO

POSIX.1-2001, POSIX.1-2008, C89, C99, SVr4, 4.3BSD.

COLOPHON

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