关于ldd3中的ioctl的调用

这几天终于把scull程序弄好了，重点是知道ioctl怎么用了，主要是要自己写一个头文件定义一些操作，这个应该是 和scull.h中定义的一模一样的。然后再在自己的应用程序中包含这个头文件，我的头文件名字为sculltest.h。具体的，我的应用程序编写如下：
 #include   <stdio.h>
#include   <fcntl.h>
#include   <sys/ioctl.h>
#include   <sys/types.h>
#include   <linux/kdev_t.h>
#include   <stdlib.h>
#include  "sculltest.h"
/*   device   path   */
char   path[]   =   "/dev/scull0";
char   buf[128];
char   temp[128];
int   main()
{
int  temp11,temp22;
int   f   =   open(path,   O_RDWR);
if   (f   ==   -1)
{
printf("device   open   error!/n");
return   1;
}
ioctl(f,SCULL_IOCGQUANTUM,&temp11);
printf("quantum is %d/n" , temp11);
printf("quantum set is /n" );
temp11 = 0;
scanf("%d",&temp11);
ioctl(f,SCULL_IOCTQUANTUM,temp11);
ioctl(f,SCULL_IOCGQUANTUM,&temp22);
printf("quantum is %d/n" , temp22);



printf("Input   a   string   to   write   device   /n");
scanf("%s",   buf);
write(f,   buf,   4); /*   device   wirte   */

printf("Read   the   string   from   device.../n");
read(f,   temp,   128); /*   device   read   */
printf("%s/n",   buf);

close(f);
}


sculltest.h文件内容如下：
/* Use 'k' as magic number */
#define SCULL_IOC_MAGIC  'k'
/* Please use a different 8-bit number in your code */

#define SCULL_IOCRESET    _IO(SCULL_IOC_MAGIC, 0)

/*
 * S means "Set" through a ptr,
 * T means "Tell" directly with the argument value
 * G means "Get": reply by setting through a pointer
 * Q means "Query": response is on the return value
 * X means "eXchange": switch G and S atomically
 * H means "sHift": switch T and Q atomically
 */
#define SCULL_IOCSQUANTUM _IOW(SCULL_IOC_MAGIC,  1, int)
#define SCULL_IOCSQSET    _IOW(SCULL_IOC_MAGIC,  2, int)
#define SCULL_IOCTQUANTUM _IO(SCULL_IOC_MAGIC,   3)
#define SCULL_IOCTQSET    _IO(SCULL_IOC_MAGIC,   4)
#define SCULL_IOCGQUANTUM _IOR(SCULL_IOC_MAGIC,  5, int)
#define SCULL_IOCGQSET    _IOR(SCULL_IOC_MAGIC,  6, int)
#define SCULL_IOCQQUANTUM _IO(SCULL_IOC_MAGIC,   7)
#define SCULL_IOCQQSET    _IO(SCULL_IOC_MAGIC,   8)
#define SCULL_IOCXQUANTUM _IOWR(SCULL_IOC_MAGIC, 9, int)
#define SCULL_IOCXQSET    _IOWR(SCULL_IOC_MAGIC,10, int)
#define SCULL_IOCHQUANTUM _IO(SCULL_IOC_MAGIC,  11)
#define SCULL_IOCHQSET    _IO(SCULL_IOC_MAGIC,  12)

/*
 * The other entities only have "Tell" and "Query", because they're
 * not printed in the book, and there's no need to have all six.
 * (The previous stuff was only there to show different ways to do it.
 */
/* ... more to come */

#define SCULL_IOC_MAXNR 14

呵呵，就ok了，呵呵，好好学习，总会感觉到自己在进步。