utmp.c
1.42 KB
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/* utmp.c -- Replacements for {set,get,end}utmp functions
Copyright (C) 2002, 2009 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public
Licensealong with this program; if not, write to the Free
SoftwareFoundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
MA 02110-1301 USA. */
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <sys/types.h>
#include <sys/time.h>
#include <utmp.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>
#include <stdio.h>
static char *utmp_name = PATH_UTMP;
static int fd = -1;
static struct utmp ut;
void
endutent ()
{
if (fd > 0)
close (fd);
fd = -1;
}
void
setutent ()
{
endutent ();
if ((fd = open (utmp_name, O_RDWR)) < 0
&& ((fd = open (utmp_name, O_RDONLY)) < 0))
perror ("setutent: Can't open utmp file");
}
struct utmp *
getutent ()
{
if (fd < 0)
setutent ();
if (fd < 0 || read (fd, &ut, sizeof ut) != sizeof ut)
return NULL;
return &ut;
}