xref: /csrg-svn/lib/libc/string/ffs.c (revision 30423)
1 /*
2  * Copyright (c) 1987 Regents of the University of California.
3  * All rights reserved.  The Berkeley software License Agreement
4  * specifies the terms and conditions for redistribution.
5  */
6 
7 #if defined(LIBC_SCCS) && !defined(lint)
8 static char sccsid[] = "@(#)ffs.c	5.1 (Berkeley) 01/27/87";
9 #endif LIBC_SCCS and not lint
10 
11 /*
12  * ffs -- vax ffs instruction
13  */
14 ffs(mask)
15 	register long mask;
16 {
17 	register int cnt;
18 
19 	if (mask == 0)
20 		return(0);
21 	for (cnt = 1; !(mask & 1); cnt++)
22 		mask >>= 1;
23 	return(cnt);
24 }
25