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 32 static void usage(void) 33 { 34 fprintf(stderr, _("Usage: %s disk\n"), progname); 35 exit(1); 36 } 37 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
