1 static char Sccsid[] = "@(#)substr.c	1.2	02/15/87";
2 /*
3 	Place the `len' length substring of `as' starting at `as[origin]'
4 	in `aresult'.
5 	Return `aresult'.
6 
7   Note: The copying of as to aresult stops if either the
8 	specified number (len) characters have been copied,
9 	or if the end of as is found.
10 	A negative len generally guarantees that everything gets copied.
11 */
12 
13 char *substr(as, aresult, origin, len)
14 char *as, *aresult;
15 int origin;
16 register unsigned len;
17 {
18 	register char *s, *result;
19 
20 	s = as + origin;
21 	result = aresult;
22 	++len;
23 	while (--len && (*result++ = *s++)) ;
24 	if (len == 0)
25 		*result = 0;
26 	return(aresult);
27 }
28