怎么通过 /proc/scsi/usb-storage来确定u盘是/dev/sdb还是sdc?

[袁保康]

我知道通过 /proc/scsi/usb-storage来确定是否有u盘插入如下：
root@kangear:~# ls /proc/scsi/usb-storage
13
有数字就代表，有U盘插入。再看：
root@kangear:~# cat /proc/partitions
major minor #blocks name

8 0 488386584 sda
8 1 51740608 sda1
8 2 76911648 sda2
8 3 51702784 sda3
8 4 1 sda4
8 5 999424 sda5
8 6 153889816 sda6
8 7 153133056 sda7
11 0 1048575 sr0
8 16 2009600 sdb
8 17 2008064 sdb1
root@kangear:~#
但是上边的“13”的这里的“sdb”好像没有什么联系呀，怎么让其对应起来呢？

（问题就是，1要判断U盘的插入 2确定该U盘的设备节点如：/dev/sdb）
上边的检测方法是在http://bbs.csdn.net/topics/360221740#post-371235029看到的。

[袁保康]

1. check if /proc/scsi/usb-storage-# exist or not 2. if exist. check if /proc/scsi/usb-storage-#/# exist or not 3. if exist. check the file /proc/scsi/usb-storage-#/# if it says Attach: Yes 4. if Yes. the # can be converted to device name: 0 = sda, 1=sdb, 2=sdc 5. But I don't know which USB port it connects to. and you don't need to know also. for example: /proc/scsi/usb-storage-0/0 says Attach: No, then /dev/sda is not attached /proc/scsi/usb-storage-1/1 says Attach: Yes, then it is attached, you can mount it. If you plug in usb storage with brandname A first, the it is usb-storage-0, then you unplug it, but that directory still exists, and now you plug in Brandname B, the storage-1 directory will be created, and storage-0 is still there. 我又看一下，上边的红色的对应关系似乎不太行，我得到的值都是13了怎么对应吗？

[袁保康]

从这里看出：http://bbs.csdn.net/topics/250026141 上边方法适用于2.4的内核，2.6以上的就不适合了。

[袁保康]

引用 3 楼 linlan999 的回复:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <sys/un.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <linux/types.h>
#include <linux/netlink.h>
#include <errno.h>
 
static int init_hotplug_sock(void)
{
    struct sockaddr_nl snl;
    const int buffersize = 16 * 1024 * 1024;
    int retval;
 
    memset(&snl, 0x00, sizeof(struct sockaddr_nl));
    snl.nl_family = AF_NETLINK;
    snl.nl_pid = getpid();
    snl.nl_groups = 1;
 
    int hotplug_sock = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT);
    if (hotplug_sock == -1) {
        printf("error getting socket: %s", strerror(errno));
        return -1;
    }
 
    /* set receive buffersize */
    setsockopt(hotplug_sock, SOL_SOCKET, SO_RCVBUFFORCE, &buffersize, sizeof(buffersize));
 
    retval = bind(hotplug_sock, (struct sockaddr *) &snl, sizeof(struct sockaddr_nl));
    if (retval < 0) {
        printf("bind failed: %s", strerror(errno));
        close(hotplug_sock);
        hotplug_sock = -1;
        return -1;
    }
 
    return hotplug_sock;
}
 
#define UEVENT_BUFFER_SIZE      2048
 
int main(int argc, char* argv[])
{
         int hotplug_sock       = init_hotplug_sock();
        
         while(1)
         {
                   char buf[UEVENT_BUFFER_SIZE*2] = {0};
                   recv(hotplug_sock, &buf, sizeof(buf), 0); 
                   printf("%s/n", buf);
         }
 
         return 0;
}
 
编译：
gcc -g hotplug.c -o hotplug_monitor

在网上搜的

很好，谢谢呀！ 我当时用这个方法： 先ls /proc/scsi/usb-storage/ 得到一个数A 然后ls /sys/class/scsi_device/$(A):0:0:0/device/block/ ($(A)是前一步得到了数) 这样就得到了sdb 或者是sdn了。

[linlan999]

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <sys/un.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <linux/types.h>
#include <linux/netlink.h>
#include <errno.h>
 
static int init_hotplug_sock(void)
{
    struct sockaddr_nl snl;
    const int buffersize = 16 * 1024 * 1024;
    int retval;
 
    memset(&snl, 0x00, sizeof(struct sockaddr_nl));
    snl.nl_family = AF_NETLINK;
    snl.nl_pid = getpid();
    snl.nl_groups = 1;
 
    int hotplug_sock = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT);
    if (hotplug_sock == -1) {
        printf("error getting socket: %s", strerror(errno));
        return -1;
    }
 
    /* set receive buffersize */
    setsockopt(hotplug_sock, SOL_SOCKET, SO_RCVBUFFORCE, &buffersize, sizeof(buffersize));
 
    retval = bind(hotplug_sock, (struct sockaddr *) &snl, sizeof(struct sockaddr_nl));
    if (retval < 0) {
        printf("bind failed: %s", strerror(errno));
        close(hotplug_sock);
        hotplug_sock = -1;
        return -1;
    }
 
    return hotplug_sock;
}
 
#define UEVENT_BUFFER_SIZE      2048
 
int main(int argc, char* argv[])
{
         int hotplug_sock       = init_hotplug_sock();
        
         while(1)
         {
                   char buf[UEVENT_BUFFER_SIZE*2] = {0};
                   recv(hotplug_sock, &buf, sizeof(buf), 0); 
                   printf("%s/n", buf);
         }
 
         return 0;
}
 
编译：
gcc -g hotplug.c -o hotplug_monitor

在网上搜的