一、实现单向链表的操作，创建 、删除、插入、查找

指针链表这货，让我焦作了一整天。终于弄好了。 有链表的创建，清空，从末尾添加。等功能。

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

typedef struct _DEV_LIST{

    int fd;
    unsigned char UUID[8];
    struct _DEV_LIST* Next;

}DEV_LIST,*pDEV_LIST;



DEV_LIST *CreatNode(void){

    DEV_LIST *pNode;

    pNode = (DEV_LIST *)malloc(sizeof(DEV_LIST));
    if(pNode == NULL)printf("内存分配失败\n");
    pNode->fd = 0;
    memset(pNode->UUID,0,sizeof(pNode->UUID));
    pNode->Next = NULL;

    return pNode;
}




void PrintfList(DEV_LIST* pHead){
    int i;
    if(NULL == pHead) //链表为空
    {
        printf("PrintList函数执行，链表为空\n");
    }
    else
    {
        while(NULL != pHead)
        {
            printf("fd=%d ",pHead->fd);
            for(i=0;i<8;i++)
            printf("UUID%d =%d \n",i,pHead->UUID[i]);
            pHead = pHead->Next;
        }
        printf("\n");
    }
}

int Add_Node(DEV_LIST** pHead)
{
    DEV_LIST *pTemp;
    if(*pHead == NULL) {
        *pHead = CreatNode();
        return 0;
    }
    pTemp = *pHead;
    while(pTemp->Next != NULL){
        pTemp = pTemp->Next;
    }
    pTemp->Next = CreatNode();
    return 0;
}

int Add_Node_End(DEV_LIST** pHead, DEV_LIST** pNode)
{
    DEV_LIST *pTemp;
    if(*pHead == NULL) {
        *pHead = CreatNode();
        (*pHead)->fd = (*pNode)->fd;
        memcpy((*pHead)->UUID ,(*pNode)->UUID,sizeof((*pHead)->UUID ));

        printf("List null\n");
        return 0;
    }
    pTemp = *pHead;
    while(pTemp->Next != NULL){
        pTemp = pTemp->Next;
    }
    pTemp->Next = *pNode;

    return 0;
}


int ClearList(DEV_LIST** pHead){
    DEV_LIST* pNext;

    if (*pHead == NULL) {
        return 0;
    }
    while((*pHead) != NULL){
        pNext = (*pHead)->Next;
        free(*pHead);
        *pHead = pNext;
    }
    return 0;
}


int GetDevNumber(DEV_LIST* pHead)
{
    int num=0;
    while(pHead) {
       num ++;
       pHead = pHead->Next ;
     }
    return num;
}



int main()
{
    DEV_LIST *pHead;
    DEV_LIST *pNode;

    pHead = NULL;
    pNode = NULL;
    printf("------------------------------\n");
    pNode = CreatNode();
    pNode->fd = 1;
    memset(pNode->UUID,1,sizeof(pNode->UUID));
    Add_Node_End(&pHead,&pNode);

    pNode = CreatNode();
    pNode->fd = 2;
    memset(pNode->UUID,2,sizeof(pNode->UUID));
    Add_Node_End(&pHead,&pNode);

    PrintfList(pHead);

    printf("GetDevNumber = %d\n",GetDevNumber(pHead));

    printf("---------------clear---------------\n");
    ClearList(&pHead);
    PrintfList(pHead);

}