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#include "stdafx.h"
#include "malloc.h"
#include "string"
typedef struct FileList{
int num;
struct FileList *pnext;
}FileList;
int main()
{
FileList *first_file;
FileList *last_file,*file;
int num;
first_file = NULL;
last_file = first_file;
while(1)
{
printf("please input num\n");
scanf("%d",&num);
if (num<0)
{
printf("quit");
return -1;
}
file = (FileList *)malloc(sizeof(FileList));
memset(file,0,sizeof(FileList));
file->num=num;
last_file=file;
last_file=file->pnext;
}
return 0;
}
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <time.h>
#define PRINT(msg) print(msg)
void print(const char *msg)
{
printf("%s[%d]:%s\r\n", __FUNCTION__, __LINE__, msg);
}
typedef struct _LinkList
{
int data;
struct _LinkList *pnext;
}Linklist;
int main(void)
{
int i = 0;
int data = 0;
Linklist *first_file = NULL, *last_file = NULL;
Linklist *file = NULL;
srand(time(NULL));
while(i++ < 10)
{
data = (rand() % 1000 + i)/i;
file = (Linklist *)malloc(sizeof(Linklist));
if(file == NULL)
{
PRINT("alloc memory failed.\n");
}
file->data = data;
file->pnext = NULL;
if(first_file == NULL)
{
first_file = file;
}
if(last_file == NULL)
{
last_file = file;
}
else
{
last_file->pnext = file;
last_file = file;
}
}
while(first_file != NULL)
{
printf("%d ", first_file->data);
first_file = first_file->pnext;
}
printf("\n");
}
last_file=file;
last_file=file->pnext;
替换为下面句
file->pnext = first_file;
first_file = file;
over//将c:\\tmp文件夹下的所有文件的内容全部放到用malloc分配的内存中
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <io.h>
struct FB {
char fn[256];
size_t fl;
char *b;
struct FB *next;
struct FB *prev;
} *fh,*fb,*ft;
char ln[256];
char fpn[256];
FILE *af;
FILE *f;
int L,n;
int main() {
system("dir /b /a-d c:\\tmp\\*.* >c:\\allfn.txt");
af=fopen("c:\\allfn.txt","r");
if (NULL==af) {
printf("Can not open file c:\\allfn.txt!\n");
return 1;
}
fh=NULL;
fb=NULL;
n=0;
while (1) {
if (NULL==fgets(ln,256,af)) break;
L=strlen(ln);
if ('\n'==ln[L-1]) ln[L-1]=0;
printf("read %s\n",ln);
strcpy(fpn,"c:\\tmp\\");
strcat(fpn,ln);
ft=(struct FB *)malloc(sizeof(struct FB));
if (NULL==ft) {
printf("Can not malloc ft!\n");
fclose(af);
return 2;//之前的malloc在main退出后由操作系统自动free
}
printf("ft[%d]==%p\n",n,ft);
strcpy(ft->fn,fpn);
f=fopen(fpn,"rb");
if (NULL==f) {
printf("Can not open file %s!\n",fpn);
fclose(af);
return 3;//之前的malloc在main退出后由操作系统自动free
}
ft->fl=_filelength(fileno(f));
ft->b=malloc(ft->fl);
if (NULL==ft->b) {
printf("Can not malloc ft->b!\n");
fclose(f);
fclose(af);
return 4;//之前的malloc在main退出后由操作系统自动free
}
printf("ft[%d]->b==%p\n",n,ft->b);
if (ft->fl!=fread(ft->b,1,ft->fl,f)) {
printf("fread error!\n");
fclose(f);
fclose(af);
return 5;//之前的malloc在main退出后由操作系统自动free
}
fclose(f);
ft->next=NULL;
if (NULL==fh) {
ft->prev=NULL;
fh=ft;
} else {
fb->next=ft;
ft->prev=fb;
}
fb=ft;
n++;
}
fclose(af);
printf("-----list-----\n");
for (ft=fh;NULL!=ft;ft=ft->next) {
printf("%8d %s\n",ft->fl,ft->fn);
if (NULL!=ft) fb=ft;
}
printf("-----free-----\n");
n--;
if (NULL!=fh) {
for (ft=fb->prev;NULL!=ft;ft=ft->prev) {
if (NULL!=ft->next->b) {
printf("ft[%d]->b==%p\n",n,ft->next->b);
free(ft->next->b);
}
if (NULL!=ft->next) {
printf("ft[%d]==%p\n",n,ft->next);
free(ft->next);
}
n--;
}
if (NULL!=fh->b) {
printf("ft[0]->b==%p\n",fh->b);
free(fh->b);
}
printf("ft[0]==%p\n",fh);
free(fh);
}
return 0;
}
//C:\tmp\tmp\Debug>dir /a-d c:\tmp
// 驱动器 C 中的卷是 C_HD5_1
// 卷的序列号是 1817-D526
//
// c:\tmp 的目录
//
//找不到文件
//
//C:\tmp\tmp\Debug>tmp
//找不到文件
//-----list-----
//-----free-----
//
//C:\tmp\tmp\Debug>dir /a-d c:\tmp
// 驱动器 C 中的卷是 C_HD5_1
// 卷的序列号是 1817-D526
//
// c:\tmp 的目录
//
//2011-06-30 18:04 44,840 my_c.rar
//2011-06-30 17:18 1,036 err.frm
//2011-06-30 14:32 14,243 出租.txt
//2011-06-28 12:08 23,681 MSDN98书签.txt
// 4 个文件 83,800 字节
// 0 个目录 17,041,870,848 可用字节
//
//C:\tmp\tmp\Debug>tmp
//read my_c.rar
//ft[0]==00421800
//ft[0]->b==00520068
//read err.frm
//ft[1]==00421670
//ft[1]->b==0052AFC0
//read 出租.txt
//ft[2]==00421530
//ft[2]->b==00378F28
//read MSDN98书签.txt
//ft[3]==004213F0
//ft[3]->b==0052B3F8
//-----list-----
// 44840 c:\tmp\my_c.rar
// 1036 c:\tmp\err.frm
// 14243 c:\tmp\出租.txt
// 23681 c:\tmp\MSDN98书签.txt
//-----free-----
//ft[3]->b==0052B3F8
//ft[3]==004213F0
//ft[2]->b==00378F28
//ft[2]==00421530
//ft[1]->b==0052AFC0
//ft[1]==00421670
//ft[0]->b==00520068
//ft[0]==00421800
//
//C:\tmp\tmp\Debug>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
typedef struct FileList{
int num;
struct FileList *pnext;
}FileList;
void walk(FileList *head)
{
FileList *file;
for (file = head; file; file = file->pnext) {
printf("%p:%d\n", file, file->num);
}
}
int main()
{
FileList *first_file;
FileList *last_file,*file;
int num;
first_file = NULL;
last_file = first_file;
while(1)
{
printf("please input num\n");
scanf("%d",&num);
if (num<0)
{
break;
printf("quit");
return -1;
}
file = (FileList *)malloc(sizeof(FileList));
memset(file,0,sizeof(FileList));
file->num=num;
/*
last_file=file;
last_file=file->pnext;
*/
if (first_file == NULL) {
first_file = last_file = file;
} else {
last_file->pnext = file;
last_file = file;
}
}
walk(first_file);
return 0;
}
if (last_file != NULL) {
last_file->pnext = file;
}
last_file = file;
#include"stdio.h"
first_file = first_file ? first_file : file;
last_file = last_file ? (last_file->pnext = file) : file;
typedef struct FileList{
int num;
struct FileList *pnext;
}FileList;
int main()
{
FileList *first_file=NULL;
FileList *last_file=NULL,*file=NULL;
int num;
while(1)
{
printf("please input num\n");
scanf("%d",&num);
if (num<0)
{
printf("quit");
return -1;
}
file = (FileList *)malloc(sizeof(FileList));
if (NULL!=file)
{
memset(file,0,sizeof(FileList));
file->num=num;
file->pnext=NULL;
if (NULL == first_file)
{
first_file=file;
last_file =file;
}
else
{
last_file->pnext = file;
}
last_file=last_file->pnext;
}
else
{
printf("malloc failed\n")
return 1;
}
}
return 0;
}