1 /*
2 **  USEFUL.H -- Some useful stuff.
3 **
4 **	@(#)useful.h	3.2	08/09/81
5 */
6 
7 # define bool	char
8 # define TRUE	1
9 # define FALSE	0
10 
11 # ifndef NULL
12 # define NULL	0
13 # endif NULL
14 
15 # define setbit(bit, word)	(word |= bit)
16 # define clrbit(bit, word)	(word &= ~bit)
17 # define bitset(bit, word)	((word) & (bit))
18 
19 /* define the types of some common functions */
20 extern char	*strcpy();
21 extern char	*strcat();
22 extern char	*malloc();
23 extern char	*index(), *rindex();
24 extern int	errno;
25 extern char	*sprintf();
26 extern long	time();
27 extern char	*ctime();
28 # ifndef V6
29 extern char	*getenv();
30 # endif
31