usr/src/lib/libutil/logwtmp.c

/*
 * Copyright (c) 1988 The Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that the above copyright notice and this paragraph are
 * duplicated in all such forms and that any documentation,
 * advertising materials, and other materials related to such
 * distribution and use acknowledge that the software was developed
 * by the University of California, Berkeley.  The name of the
 * University may not be used to endorse or promote products derived
 * from this software without specific prior written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)logwtmp.c   5.4 (Berkeley) %G%";
#endif /* LIBC_SCCS and not lint */

#include <sys/types.h>
#include <sys/file.h>
#include <sys/time.h>
#include <sys/stat.h>
#include <utmp.h>

logwtmp(line, name, host)
        char *line, *name, *host;
{
        struct utmp ut;
        struct stat buf;
        int fd;
        time_t time();
        char *strncpy();

        if ((fd = open(_PATH_WTMP, O_WRONLY|O_APPEND, 0)) < 0)
                return;
        if (fstat(fd, &buf) == 0) {
                (void) strncpy(ut.ut_line, line, sizeof(ut.ut_line));
                (void) strncpy(ut.ut_name, name, sizeof(ut.ut_name));
                (void) strncpy(ut.ut_host, host, sizeof(ut.ut_host));
                (void) time(&ut.ut_time);
                if (write(fd, (char *)&ut, sizeof(struct utmp)) !=
                    sizeof(struct utmp))
                        (void) ftruncate(fd, buf.st_size);
        }
        (void) close(fd);
}