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/************************************************************ 
 *        IBM PC "C" Bulletin Board                         * 
 *        Tulsa, OK    918-664-8737                         * 
 *        Lynn Long, SYSOP   300/1200 XMODEM                * 
 ************************************************************/ 
 
 
 
 
char *strcpy(dest, src) 
register char *dest, *src; 
{ 
        char *sav; 
 
        sav = dest; 
        while (*dest++ = *src++) 
                ; 
        return sav; 
} 
 
char *strncpy(dest, src, len) 
register char *dest, *src; 
{ 
        char *sav; 
 
        sav = dest; 
        while (len--) { 
                if ((*dest++ = *src++) == 0) { 
                        while (len--) 
                                *dest++ = 0; 
                        break; 
                } 
        } 
        return sav; 
} 
 
char *strcat(dest, src) 
register char *dest, *src; 
{ 
        char *sav; 
 
        sav = dest; 
        while (*dest) 
                ++dest; 
        while (*dest++ = *src++) 
                ; 
        return sav; 
} 
 
char *strncat(dest, src, len) 
register char *dest, *src; 
{ 
        char *sav; 
 
        sav = dest; 
        while (*dest) 
                ++dest; 
        do { 
                if (len-- == 0) { 
                        *dest = 0; 
                        break; 
                } 
        } while (*dest++ = *src++); 
        return sav; 
} 
 
strcmp(a, b) 
register char *a, *b; 
{ 
        int i; 
 
        while ((i = *a - *b++) == 0 && *a++) 
                ; 
        return i; 
} 
 
strncmp(a, b, len) 
register char *a, *b; 
{ 
        int i = 0; 
 
        while (len-- && (i = *a - *b++) == 0 && *a++) 
                ; 
        return i; 
} 
 
strlen(str) 
register char *str; 
{ 
        register int len = 0; 
 
        while (*str++) 
                ++len; 
        return len; 
} 
 
char *index(str, c) 
register char *str; register int c; 
{ 
        while (*str) { 
                if (*str == c) 
                        return str; 
                ++str; 
        } 
        return (char *)0; 
} 
 
char *rindex(str, c) 
register char *str; int c; 
{ 
        register char *cp; 
 
        for (cp = str ; *cp++ ; ) 
                ; 
        while (cp > str) 
                if (*--cp == c) 
                        return cp; 
        return (char *)0; 
}