udev笔记

1.udevd的主配置文件是/etc/udev/udev.conf

2.使用udev来监听U的hot-plug事件

 1 #include <stdio.h>  
 2 #include <stdlib.h>  
 3 #include <string.h>  
 4 #include <ctype.h>  
 5 #include <sys/un.h>  
 6 #include <sys/ioctl.h>  
 7 #include <sys/socket.h>  
 8 #include <linux/types.h>  
 9 #include <linux/netlink.h>  
10 #include <errno.h>  
11 #include <unistd.h>  
12 #include <arpa/inet.h>  
13 #include <netinet/in.h>
14 
15 
16 static int init_hotplug_sock(void)
17 {
18     struct sockaddr_nl snl;
19     const int buffersize = 16 * 1024 * 1024;
20     int retval;
21  
22     memset(&snl, 0x00, sizeof(struct sockaddr_nl));
23     snl.nl_family = AF_NETLINK;
24     snl.nl_pid = getpid();
25     snl.nl_groups = 1;
26  
27     int hotplug_sock = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT);
28     if (hotplug_sock == -1) {
29         printf("error getting socket: %s", strerror(errno));
30         return -1;
31     }
32  
33     /* set receive buffersize */
34     setsockopt(hotplug_sock, SOL_SOCKET, SO_RCVBUFFORCE, &buffersize, sizeof(buffersize));
35  
36     retval = bind(hotplug_sock, (struct sockaddr *) &snl, sizeof(struct sockaddr_nl));
37     if (retval < 0) {
38         printf("bind failed: %s", strerror(errno));
39         close(hotplug_sock);
40         hotplug_sock = -1;
41         return -1;
42     }
43  
44     return hotplug_sock;
45 }
46  
47 #define UEVENT_BUFFER_SIZE 2048
48  
49 int main(int argc, char* argv[])
50 {
51      int hotplug_sock = init_hotplug_sock();
52     
53      while(1)
54      {
55            char buf[UEVENT_BUFFER_SIZE*2] = {0};
56            recv(hotplug_sock, &buf, sizeof(buf), 0); 
57            printf("%s\n", buf);
58      }
59 
60      return 0;
61 }

插上和拔出U盘打印：

add@/devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1
add@/devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1/1-1:1.0
add@/module/usb_storage
add@/devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1/1-1:1.0/host33
add@/devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1/1-1:1.0/host33/scsi_host/host33
add@/bus/usb/drivers/usb-storage
add@/module/uas
add@/bus/usb/drivers/uas
add@/devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1/1-1:1.0/host33/target33:0:0
add@/devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1/1-1:1.0/host33/target33:0:0/33:0:0:0
add@/devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1/1-1:1.0/host33/target33:0:0/33:0:0:0/scsi_disk/33:0:0:0
add@/devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1/1-1:1.0/host33/target33:0:0/33:0:0:0/scsi_device/33:0:0:0
add@/devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1/1-1:1.0/host33/target33:0:0/33:0:0:0/scsi_generic/sg2
add@/devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1/1-1:1.0/host33/target33:0:0/33:0:0:0/bsg/33:0:0:0
add@/devices/virtual/bdi/8:16
add@/devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1/1-1:1.0/host33/target33:0:0/33:0:0:0/block/sdb
add@/devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1/1-1:1.0/host33/target33:0:0/33:0:0:0/block/sdb/sdb1
add@/module/nls_iso8859_1

remove@/devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1/1-1:1.0/host33/target33:0:0/33:0:0:0/bsg/33:0:0:0
remove@/devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1/1-1:1.0/host33/target33:0:0/33:0:0:0/scsi_generic/sg2
remove@/devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1/1-1:1.0/host33/target33:0:0/33:0:0:0/scsi_device/33:0:0:0
remove@/devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1/1-1:1.0/host33/target33:0:0/33:0:0:0/scsi_disk/33:0:0:0
change@/devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1/1-1:1.0/host33/target33:0:0/33:0:0:0/block/sdb
remove@/devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1/1-1:1.0/host33/target33:0:0/33:0:0:0/block/sdb/sdb1
remove@/devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1/1-1:1.0/host33/target33:0:0/33:0:0:0/block/sdb
remove@/devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1/1-1:1.0/host33/target33:0:0/33:0:0:0
remove@/devices/virtual/bdi/8:16
remove@/devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1/1-1:1.0/host33/target33:0:0
remove@/devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1/1-1:1.0/host33/scsi_host/host33
remove@/devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1/1-1:1.0/host33
remove@/devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1/1-1:1.0
remove@/devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1

3.利用udev更改网卡的名字

①通过ifconfig或者ubuntu:$ cat /sys/class/net/eth0/address来获得网卡的MAC地址：
00:0c:29:e1:b6:cd

②创建rules文件
/etc/udev/rules.d/my-network.rules
cat my-network.rules:
SUBSYSTEM=="net", ATTR{address}=="00:0c:29:e1:b6:cd", NAME="my-eth0"

然后重启，发现网卡名字从eth0变为my-eth0