//一个简单DIRECT-IO例子 (linux i386)。 JOHN SEEKER



#include <stdio.h>;

#include <sys/types.h>;

#include <sys/stat.h>;

#include <asm/fcntl.h>;

#include <unistd.h>;

#define _XOPEN_SOURCE 600

#include <stdlib.h>;



//int posix_memalign(void **memptr, size_t alignment, size_t size);

       

//#include <fcntl.h>;



char buf[4096] = "123456kasf dklasfkasfkldkladsfklafskldsfkl";

char buf1[256];

main()

{

int fd;

int i, r;

char *bp;



    r = posix_memalign(&bp, 512, 4096*8);

    printf("r = %d\n", r);

    memcpy(bp, buf, 4096);

    

    fd = open("data", O_CREAT | O_RDWR | O_TRUNC | O_DIRECT, 0644);

    

    printf("fd = %d\n", fd);

    

    r = write(fd, bp, 4096);

    printf("%d bytes written.\n", r);



    close(fd);

}