xref: /csrg-svn/lib/libutil/logout.c (revision 39179)
1 /*
2  * Copyright (c) 1988 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms are permitted
6  * provided that the above copyright notice and this paragraph are
7  * duplicated in all such forms and that any documentation,
8  * advertising materials, and other materials related to such
9  * distribution and use acknowledge that the software was developed
10  * by the University of California, Berkeley.  The name of the
11  * University may not be used to endorse or promote products derived
12  * from this software without specific prior written permission.
13  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
14  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
15  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
16  */
17 
18 #if defined(LIBC_SCCS) && !defined(lint)
19 static char sccsid[] = "@(#)logout.c	5.4 (Berkeley) 09/19/89";
20 #endif /* LIBC_SCCS and not lint */
21 
22 #include <sys/types.h>
23 #include <sys/file.h>
24 #include <sys/time.h>
25 #include <utmp.h>
26 
27 typedef struct utmp UTMP;
28 
29 logout(line)
30 	register char *line;
31 {
32 	register int fd;
33 	UTMP ut;
34 	int rval;
35 	off_t lseek();
36 	time_t time();
37 
38 	if ((fd = open(_PATH_UTMP, O_RDWR)) < 0)
39 		return(0);
40 	rval = 0;
41 	while (read(fd, (char *)&ut, sizeof(UTMP)) == sizeof(UTMP)) {
42 		if (!ut.ut_name[0] || strncmp(ut.ut_line, line, UT_LINESIZE))
43 			continue;
44 		bzero(ut.ut_name, UT_NAMESIZE);
45 		bzero(ut.ut_host, UT_HOSTSIZE);
46 		(void)time(&ut.ut_time);
47 		(void)lseek(fd, -(long)sizeof(UTMP), L_INCR);
48 		(void)write(fd, (char *)&ut, sizeof(UTMP));
49 		rval = 1;
50 	}
51 	(void)close(fd);
52 	return(rval);
53 }
54