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 <stdio.h>
17 #include <string.h>
18 #include <unistd.h>
19 #include <stdlib.h>
20 #include <fcntl.h>
21 #include <sys/ioctl.h>
22 #include <sys/mount.h>
23 #include "../misc/nls-enable.h"
24
25 /* For Linux, define BLKFLSBUF if necessary */
26 #if (!defined(BLKFLSBUF) && defined(__linux__))
27 #define BLKFLSBUF _IO(0x12,97) /* flush buffer cache */
28 #endif
29
30 const char *progname;
31
usage(void)32 static void usage(void)
33 {
34 fprintf(stderr, _("Usage: %s disk\n"), progname);
35 exit(1);
36 }
37
main(int argc,char ** argv)38 int main(int argc, char **argv)
39 {
40 int fd;
41
42 progname = argv[0];
43 if (argc != 2)
44 usage();
45
46 fd = open(argv[1], O_RDONLY, 0);
47 if (fd < 0) {
48 perror("open");
49 exit(1);
50 }
51 /*
52 * Note: to reread the partition table, use the ioctl
53 * BLKRRPART instead of BLKFSLBUF.
54 */
55 #ifdef BLKFLSBUF
56 if (ioctl(fd, BLKFLSBUF, 0) < 0) {
57 perror("ioctl BLKFLSBUF");
58 exit(1);
59 }
60 return 0;
61 #else
62 fprintf(stderr,
63 _("BLKFLSBUF ioctl not supported! Can't flush buffers.\n"));
64 return 1;
65 #endif
66 }
67