1/*
2 * flushb.c --- This routine flushes the disk buffers for a disk
3 *
4 * Copyright 1997, 2000, by Theodore Ts'o.
5 *
6 * WARNING: use of flushb on some older 2.2 kernels on a heavily loaded
7 * system will corrupt filesystems.  This program is not really useful
8 * beyond for benchmarking scripts.
9 *
10 * %Begin-Header%
11 * This file may be redistributed under the terms of the GNU Public
12 * License.
13 * %End-Header%
14 */
15
16#include "config.h"
17#include <stdio.h>
18#include <string.h>
19#include <unistd.h>
20#include <stdlib.h>
21#include <fcntl.h>
22#include <sys/ioctl.h>
23#include <sys/mount.h>
24#include "../misc/nls-enable.h"
25
26/* For Linux, define BLKFLSBUF if necessary */
27#if (!defined(BLKFLSBUF) && defined(__linux__))
28#define BLKFLSBUF	_IO(0x12,97)	/* flush buffer cache */
29#endif
30
31const char *progname;
32
33static void usage(void)
34{
35	fprintf(stderr, _("Usage: %s disk\n"), progname);
36	exit(1);
37}
38
39int main(int argc, char **argv)
40{
41	int	fd;
42
43	progname = argv[0];
44	if (argc != 2)
45		usage();
46
47	fd = open(argv[1], O_RDONLY, 0);
48	if (fd < 0) {
49		perror("open");
50		exit(1);
51	}
52	/*
53	 * Note: to reread the partition table, use the ioctl
54	 * BLKRRPART instead of BLKFSLBUF.
55	 */
56#ifdef BLKFLSBUF
57	if (ioctl(fd, BLKFLSBUF, 0) < 0) {
58		perror("ioctl BLKFLSBUF");
59		exit(1);
60	}
61	return 0;
62#else
63	fprintf(stderr,
64		_("BLKFLSBUF ioctl not supported!  Can't flush buffers.\n"));
65	return 1;
66#endif
67}
68