利用fputc 、fgetc實現文件的拷貝

int main(int argc, const char *argv[])
{FILE* rfp=fopen(argv[1],"r");FILE* wfp=fopen(argv[2],"w");if(rfp==NULL || wfp==NULL){perror("fopen");return 1;}while(1){char res=fgetc(rfp);if(feof(rfp)==1){break;}fputc(res,wfp);}fclose(rfp);fclose(wfp);return 0;
}

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將鏈表中數據拷貝到文件中，再將文件內容拷貝入鏈表

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
typedef struct Data
{char name[32];int age;int score;
}data_t;typedef struct Student
{union studata{struct Student* tail;//在頭節點里面，用來存放尾節點指針data_t val;}data;struct Student* next;
}stu_t;// 創建頭節點
stu_t* create_head()
{stu_t* head = (stu_t*)malloc(sizeof(stu_t));memset(head,0,sizeof(stu_t));head->data.tail = head;// 只有頭節點的時候，尾節點就是頭節點本身head->next = NULL;return head;
}// 創建普通節點
stu_t* create_node()
{stu_t* newnode = (stu_t*)malloc(sizeof(stu_t));memset(newnode,0,sizeof(stu_t));return newnode;
}// 向鏈表中添加一個新的節點
void insert_node(stu_t* head,data_t data)
{stu_t* newnode = create_node();newnode->data.val = data;head->data.tail->next = newnode;head->data.tail = newnode;newnode->next = NULL;
}void show(stu_t* head)
{stu_t* p = head->next;printf("學生信息如下:\n");while(p != NULL){printf("姓名:%s 年齡:%d 成績:%d\n",p->data.val.name,p->data.val.age,p->data.val.score);p = p->next;}printf("------------------\n");
}void save_stu(stu_t* head)
{FILE* fp = fopen("./1.c","w");if(fp == NULL){return;}stu_t* p = head->next;while(p != NULL){fprintf(fp,"%s %d %d\n",p->data.val.name,p->data.val.age,p->data.val.score);p = p->next;}fclose(fp);
}void load_stu(stu_t* head)
{FILE* fp = fopen("./1.c","r");if(fp == NULL){return ;}while(1){// 準備一個臨時的學生數據域，用來保存從文件中讀取到的信息data_t data = {0};int res = fscanf(fp,"%s %d %d\n",data.name,&data.age,&data.score);if(feof(fp)==1){break;}insert_node(head,data);}fclose(fp);
}int main(int argc, const char *argv[])
{stu_t* head = create_head();load_stu(head);int num=0;while(1){printf("1:添加學生\n");printf("2:查看學生信息\n");printf("3:保存學生信息\n");printf("請選擇:");scanf("%d",&num);printf("------------------\n");getchar();switch(num){case 1:{data_t data;printf("請輸入學生姓名、年齡、成績:");scanf("%s %d %d",data.name,&data.age,&data.score);printf("------------------\n");insert_node(head,data);break;}case 2:show(head);break;case 3:save_stu(head);break;default:break;}}return 0;
}

結果如下：?

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