strncmp.c

Many C samples. It is a good sample for students to learn C language.

/*  File   : strncmp.c
    Author : Richard A. O'Keefe.
    Updated: 10 April 1984
    Defines: strncmp()

    strncmp(s, t, n) compares the first n characters of s and t.
    If they are the same in the first n characters it returns 0,
    otherwise it returns the same value as strcmp(s, t) would.
*/

#include "strings.h"

int strncmp(s, t, n)
    register char *s, *t;
    register int n;
    {
	while (--n >= 0) {
	    if (*s != *t++) return s[0]-t[-1];
	    if (!*s++) return 0;
	}
	return 0;
     }