flush.c

系统迁移的源代码： http://www.diku.dk/hjemmesider/ansatte/jacobg/

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

# define _IO(x,y)   (((x)<<8)|y)
#define BLKFLSBUF  _IO(0x12,97) /* flush buffer cache */


void invalidate(char* dev)
{
	int f = open(dev,O_RDONLY);
	if(f<0)
	{
		puts("couldn't open blockdev\n");
		exit(-1);
	}

	printf("%s ioctl ret %d\n",dev,ioctl(f,BLKFLSBUF));

	close(f);
}


int main(int argc,char** argv)
{
	invalidate("/dev/hda");
	invalidate("/dev/hda2");
	invalidate("/dev/hda3");
	invalidate("/dev/loop/6");
}