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/* diskctl - control disk device driver parameters - by D.C. van Moolenbroek */
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <sys/ioctl.h>
#include <unistd.h>
#include <fcntl.h>
static void __dead
usage(void)
{
fprintf(stderr,
"usage: %s <device> <command> [args]\n"
"\n"
"supported commands:\n"
" getwcache return write cache status\n"
" setwcache [on|off] set write cache status\n"
" flush flush write cache\n",
getprogname());
exit(EXIT_FAILURE);
}
static int
open_dev(const char * dev, int flags)
{
int fd;
fd = open(dev, flags);
if (fd < 0) {
perror("open");
exit(EXIT_FAILURE);
}
return fd;
}
int
main(int argc, char ** argv)
{
int fd, val;
setprogname(argv[0]);
if (argc < 3) usage();
if (!strcasecmp(argv[2], "getwcache")) {
if (argc != 3) usage();
fd = open_dev(argv[1], O_RDONLY);
if (ioctl(fd, DIOCGETWC, &val) != 0) {
perror("ioctl");
return EXIT_FAILURE;
}
close(fd);
printf("write cache is %s\n", val ? "on" : "off");
} else if (!strcasecmp(argv[2], "setwcache")) {
if (argc != 4) usage();
if (!strcasecmp(argv[3], "on"))
val = 1;
else if (!strcasecmp(argv[3], "off"))
val = 0;
else
usage();
fd = open_dev(argv[1], O_WRONLY);
if (ioctl(fd, DIOCSETWC, &val) != 0) {
perror("ioctl");
return EXIT_FAILURE;
}
close(fd);
printf("write cache %sabled\n", val ? "en" : "dis");
} else if (!strcasecmp(argv[2], "flush")) {
if (argc != 3) usage();
fd = open_dev(argv[1], O_WRONLY);
if (ioctl(fd, DIOCFLUSH, NULL) != 0) {
perror("ioctl");
return EXIT_FAILURE;
}
close(fd);
printf("write cache flushed\n");
} else
usage();
return EXIT_SUCCESS;
}
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