操作系统文件管理系统模拟实验

文件管理系统模拟1.实验目的通过一个简单多用户文件系统的设计，加深理解文件系统的内部功能及内部实现2.实验内容为Linux系统设计一个简单的二级文件系统。

要求做到以下几点：（1）可以实现下列几条命令（至少4条）login 用户登录dir 列文件目录create 创建文件delete 删除文件open 打开文件close 关闭文件read 读文件write 写文件（2）列目录时要列出文件名、物理地址、保护码和文件长度；（3）源文件可以进行读写保护。

3.实验提示页脚内容0（1）首先应确定文件系统的数据结构：主目录、子目录及活动文件等。

主目录和子目录都以文件的形式存放于磁盘，这样便于查找和修改。

（2）用户创建的文件，可以编号存储于磁盘上。

入file0,file1,file2…并以编号作为物理地址，在目录中进行登记。

4.源代码#include<stdio.h>#include<string.h>#include<stdlib.h>#define MEM_D_SIZE 1024*1024 //总磁盘空间为1M#define DISKSIZE 1024//磁盘块的大小1K#define DISK_NUM 1024//磁盘块数目1K#define FATSIZE DISK_NUM*sizeof(struct fatitem) //FAT表大小#define ROOT_DISK_NO FATSIZE/DISKSIZE+1 //根目录起始盘块号#define ROOT_DISK_SIZE sizeof(struct direct) //根目录大小#define DIR_MAXSIZE 1024//路径最大长度为1KB#define MSD 5 //最大子目录数5#define MOFN 5//最大文件深度为5#define MAX_WRITE 1024*128//最大写入文字长度128KBstruct fatitem /* size 8*/{int item; /*存放文件下一个页脚内容1磁盘的指针*/char em_disk; /*磁盘块是否空闲标志位0 空闲*/};struct direct{/*-----文件控制快信息-----*/struct FCB{char name[9]; /*文件/目录名8位*/char property; /*属性1位目录0位普通文件*/int size; /*文件/目录字节数、盘块数)*/int firstdisk; /*文件/目录起始盘块号*/int next; /*子目录起始盘块号*/int sign; /*1是根目录0不是根目录*/}directitem[MSD+2];};struct opentable{struct openttableitem{char name[9]; /*文件名*/int firstdisk; /*起始盘块号*/int size; /*文件的大小*/ }openitem[MOFN];int cur_size; /*当前打文件的数目*/页脚内容2};struct fatitem *fat; /*FAT表*/ struct direct *root; /*根目录*/struct direct *cur_dir; /*当前目录*/struct opentable u_opentable; /*文件打开表*/int fd=-1; /*文件打开表的序号*/char *bufferdir; /*记录当前路径的名称*/char *fdisk; /*虚拟磁盘起始地址*/void initfile();void format();void enter();void halt();int create(char *name);int open(char *name);int close(char *name);int write(int fd,char *buf,int len);int read(int fd,char *buf);int del(char *name);int mkdir(char *name);int rmdir(char *name);void dir();int cd(char *name);void print();void show();void initfile(){fdisk = (char *)malloc(MEM_D_SIZE*sizeof(char)); /*申请1M空间*/页脚内容3format();}void format(){int i;FILE *fp;fat = (struct fatitem *)(fdisk+DISKSIZE); /*计算FAT表地址，引导区向后偏移1k)*//*-----初始化FAT表------------*/fat[0].item=-1; /*引导块*/fat[0].em_disk='1';for(i=1;i<ROOT_DISK_NO-1;i++) /*存放FAT表的磁盘块号*/{fat[i].item=i+1;fat[i].em_disk='1';}fat[ROOT_DISK_NO].item=-1; /*存放根目录的磁盘块号*/fat[ROOT_DISK_NO].em_disk='1';for(i=ROOT_DISK_NO+1;i<DISK_ NUM;i++){fat[i].item = -1;fat[i].em_disk = '0';}/*-----------------------------------------------*/root = (struct direct *)(fdisk+DISKSIZE+FATSIZE); /*根目录的地址*/页脚内容4/*初始化目录*//*---------指向当前目录的目录项---------*/root->directitem[0].sign = 1;root->directitem[0].firstdisk = ROOT_DISK_NO;strcpy(root->directitem[0].name, ".");root->directitem[0].next = root->directitem[0].firstdisk;root->directitem[0].property = '1';root->directitem[0].size = ROOT_DISK_SIZE;/*-------指向上一级目录的目录项---------*/root->directitem[1].sign = 1;root->directitem[1].firstdisk = ROOT_DISK_NO;strcpy(root->directitem[1].name,"..");root->directitem[1].next = root->directitem[0].firstdisk;root->directitem[1].property = '1';root->directitem[1].size = ROOT_DISK_SIZE;if((fp = fopen("disk.dat","wb"))==NULL){printf("Error:\n Cannot open file \n");return;}for(i=2;i<MSD+2;i++) /*-子目录初始化为空-*/{root->directitem[i].sign = 0;root->directitem[i].firstdisk页脚内容5= -1;strcpy(root->directitem[i].name,"");root->directitem[i].next = -1;root->directitem[i].property = '0';root->directitem[i].size = 0;}if((fp = fopen("disk.dat","wb"))==NULL){printf("Error:\n Cannot open file \n");return;}if(fwrite(fdisk,MEM_D_SIZE,1,fp)!= 1) /*把虚拟磁盘空间保存到磁盘文件中*/{printf("Error:\n File write error! \n");}fclose(fp);}void enter(){FILE *fp;int i;fdisk = (char *)malloc(MEM_D_SIZE*sizeof(char)); /*申请1M空间*/if((fp=fopen("disk.dat","rb"))= =NULL){页脚内容6printf("Error:\nCannot open file\n");return;}if(!fread(fdisk,MEM_D_SIZE,1,fp)) /*把磁盘文件disk.dat 读入虚拟磁盘空间(内存)*/{printf("Error:\nCannot read file\n");exit(0);}fat = (struct fatitem *)(fdisk+DISKSIZE); /*找到FAT表地址*/root = (struct direct *)(fdisk+DISKSIZE+FATSIZE);/*找到根目录地址*/fclose(fp);/*--------------初始化用户打开表------------------*/for(i=0;i<MOFN;i++){strcpy(u_opentable.openitem[i].name ,"");u_opentable.openitem[i].firstdisk = -1;u_opentable.openitem[i].size = 0;}u_opentable.cur_size = 0;cur_dir = root; /*当前目录为根目录*/bufferdir = (char *)malloc(DIR_MAXSIZE*sizeof(char));strcpy(bufferdir,"Root:");}页脚内容7void halt(){FILE *fp;int i;if((fp=fopen("disk.dat","wb"))= =NULL){printf("Error:\nCannot open file\n");return;}if(!fwrite(fdisk,MEM_D_SIZE,1,fp)) /*把虚拟磁盘空间(内存)内容读入磁盘文件disk.dat */{printf("Error:\nFile write error!\n");}fclose(fp);free(fdisk);free(bufferdir);return;}int create(char *name){int i,j;if(strlen(name)>8) /*文件名大于8位*/return(-1);for(j=2;j<MSD+2;j++) /*检查创建文件是否与已存在的文件重名*/页脚内容8{if(!strcmp(cur_dir->directitem[j].nam e,name))break;}if(j<MSD+2) /*文件已经存在*/return(-4);for(i=2;i<MSD+2;i++) /*找到第一个空闲子目录*/{if(cur_dir->directitem[i].firstdisk==-1 )break;}if(i>=MSD+2) /*无空目录项*/return(-2);if(u_opentable.cur_size>=MOFN) /*打开文件太多*/return(-3);for(j=ROOT_DISK_NO+1;j<DISK_NUM;j++) /*找到空闲盘块j 后退出*/{if(fat[j].em_disk=='0')break;}if(j>=DISK_NUM)return(-5);fat[j].em_disk = '1'; /*将空闲块置为已经分配*//*-----------填写目录项-----------------*/页脚内容9strcpy(cur_dir->directitem[i].name,name);cur_dir->directitem[i].firstdisk = j;cur_dir->directitem[i].size = 0;cur_dir->directitem[i].next = j;cur_dir->directitem[i].property = '0';/*---------------------------------*/fd = open(name);return 0;}int open(char *name){int i, j;for(i=2;i<MSD+2;i++) /*文件是否存在*/{if(!strcmp(cur_dir->directitem[i].nam e,name))break;}if(i>=MSD+2)return(-1);/*--------是文件还是目录-----------------------*/if(cur_dir->directitem[i].property =='1')return(-4);/*--------文件是否打开-----------------------*/for(j=0;j<MOFN;j++){页脚内容10if(!strcmp(u_opentable.openitem[j].na me,name))break;}if(j<MOFN) /*文件已经打开*/return(-2);if(u_opentable.cur_size>=MOFN) /*文件打开太多*/return(-3);/*--------查找一个空闲用户打开表项-----------------------*/for(j=0;j<MOFN;j++){if(u_opentable.openitem[j].firstdisk= =-1)break;}/*--------------填写表项的相关信息------------------------*/u_opentable.openitem[j].firstdisk = cur_dir->directitem[i].firstdisk;strcpy(u_opentable.openitem[j].name,nam e);u_opentable.openitem[j].size = cur_dir->directitem[i].size;u_opentable.cur_size++;/*----------返回用户打开表表项的序号--------------------------*/return(j);}int close(char *name){int i;页脚内容11for(i=0;i<MOFN;i++){if(!strcmp(u_opentable.openitem[i].na me,name))break;}if(i>=MOFN)return(-1);/*-----------清空该文件的用户打开表项的内容---------------------*/strcpy(u_opentable.openitem[i].name,"");u_opentable.openitem[i].firstdisk = -1;u_opentable.openitem[i].size = 0;u_opentable.cur_size--;return 0;}int write(int fd, char *buf, int len){char *first;int item, i, j, k;int ilen1, ilen2, modlen, temp;/*----------用$ 字符作为空格# 字符作为换行符-----------------------*/ char Space = 32;char Endter= '\n';for(i=0;i<len;i++){if(buf[i] == '$')buf[i] = Space;页脚内容12else if(buf[i] == '#')buf[i] = Endter;}/*----------读取用户打开表对应表项第一个盘块号-----------------------*/item = u_opentable.openitem[fd].firstdisk;/*-------------找到当前目录所对应表项的序号-------------------------*/for(i=2;i<MSD+2;i++){if(cur_dir->directitem[i].firstdisk==it em)break;}temp = i; /*-存放当前目录项的下标-*//*------找到的item 是该文件的最后一块磁盘块-------------------*/ while(fat[item].item!=-1){item =fat[item].item; /*-查找该文件的下一盘块--*/}/*-----计算出该文件的最末地址-------*/first = fdisk+item*DISKSIZE+u_opentable.openit em[fd].size%DISKSIZE;/*-----如果最后磁盘块剩余的大小大于要写入的文件的大小-------*/ if(DISKSIZE-u_opentable.openite m[fd].size%DISKSIZE>len)页脚内容13{strcpy(first,buf);u_opentable.openitem[fd].size = u_opentable.openitem[fd].size+len;cur_dir->directitem[temp].size = cur_dir->directitem[temp].size+len;}else{for(i=0;i<(DISKSIZE-u_opentable.ope nitem[fd].size%DISKSIZE);i++){/*写一部分内容到最后一块磁盘块的剩余空间(字节)*/first[i] = buf [i];}/*-----计算分配完最后一块磁盘的剩余空间(字节) 还剩下多少字节未存储-------*/ilen1 = len-(DISKSIZE-u_opentable.openitem[fd].si ze%DISKSIZE);ilen2 = ilen1/DISKSIZE;modlen = ilen1%DISKSIZE;if(modlen>0)ilen2 = ilen2+1; /*--还需要多少块磁盘块-*/for(j=0;j<ilen2;j++){for(i=ROOT_DISK_NO+1;i<DISK_NUM;i ++)/*寻找空闲磁盘块*/{if(fat[i].em_disk=='0')break;页脚内容14}if(i>=DISK_NUM) /*--如果磁盘块已经分配完了-*/return(-1);first = fdisk+i*DISKSIZE; /*--找到的那块空闲磁盘块的起始地址-*/if(j==ilen2-1) /*--如果是最后要分配的一块-*/{for(k=0;k<len-(DISKSIZE-u_opentable .openitem[fd].size%DISKSIZE)-j*DISKSIZE;k ++)first[k] = buf[k];}else/*-如果不是要最后分配的一块--*/{for(k=0;k<DISKSIZE;k++)first[k] =buf[k];}fat[item].item = i; /*--找到一块后将它的序号存放在上一块的指针中-*/fat[i].em_disk = '1'; /*--置找到的磁盘快的空闲标志位为已分配-*/fat[i].item = -1; /*--它的指针为-1 (即没有下一块)-*/}/*--修改长度-*/u_opentable.openitem[fd].size = u_opentable.openitem[fd].size+len;cur_dir->directitem[temp].size =页脚内容15cur_dir->directitem[temp].size+len;}return 0;}int read(int fd, char *buf){int len = u_opentable.openitem[fd].size;char *first;int i, j, item;int ilen1, modlen;item = u_opentable.openitem[fd].firstdisk;ilen1 = len/DISKSIZE;modlen = len%DISKSIZE;if(modlen!=0)ilen1 = ilen1+1; /*--计算文件所占磁盘的块数-*/first = fdisk+item*DISKSIZE; /*--计算文件的起始位置-*/for(i=0;i<ilen1;i++){if(i==ilen1-1) /*--如果在最后一个磁盘块-*/{for(j=0;j<len-i*DISKSIZE;j++)buf[i*DISKSIZE+j] = first[j];}else /*--不在最后一块磁盘块-*/{页脚内容16for(j=0;j<len-i*DISKSIZE;j++)buf[i*DISKSIZE+j] = first[j];item = fat[item].item; /*-查找下一盘块-*/first = fdisk+item*DISKSIZE;}}return 0;}int del(char *name){int i,cur_item,item,temp;for(i=2;i<MSD+2;i++) /*--查找要删除文件是否在当前目录中-*/{if(!strcmp(cur_dir->directitem[i].nam e,name))break;}cur_item = i; /*--用来保存目录项的序号,供释放目录中-*/if(i>=MSD+2) /*--如果不在当前目录中-*/return(-1);if(cur_dir->directitem[cur_item]. property!='0') /*--如果删除的(不)是目录-*/return(-3);for(i=0;i<MOFN;i++) /*--如果文件打开,则不能删除,退出-*/页脚内容17{if(!strcmp(u_opentable.openitem[i].na me,name))return(-2);}item = cur_dir->directitem[cur_item].firstdisk;/* --该文件的起始盘块号-*/while(item!=-1) /*--释放空间,将FAT表对应项进行修改-*/{temp = fat[item].item;fat[item].item = -1;fat[item].em_disk = '0';item = temp;}/*-----------------释放目录项-----------------------*/cur_dir->directitem[cur_item].si gn = 0;cur_dir->directitem[cur_item].fir stdisk = -1;strcpy(u_opentable.openitem[cur _item].name,"");cur_dir->directitem[cur_item].next = -1;cur_dir->directitem[cur_item].property = '0';cur_dir->directitem[cur_item].siz e = 0;return 0;}int mkdir(char *name){int i,j;页脚内容18struct direct *cur_mkdir;if(!strcmp(name,"."))return(-4);if(!strcmp(name,".."))return(-4);if(strlen(name)>8) /*-如果目录名长度大于8位-*/return(-1);for(i=2;i<MSD+2;i++) /*-如果有空闲目录项退出-*/{if(cur_dir->directitem[i].firstdisk==-1 )break;}if(i>=MSD+2) /*-目录/文件已满-*/return(-2);for(j=2;j<MSD+2;j++) /*-判断是否有重名-*/{if(!strcmp(cur_dir->directitem[j].nam e,name))break;}if(j<MSD+2) /*-如果有重名-*/return(-3);for(j=ROOT_DISK_NO+1;j<DISK_ NUM;j++) /*-找到空闲磁盘块j 后退出-*/{if(fat[j].em_disk=='0')break;页脚内容19}if(j>=DISK_NUM)return(-5);fat[j].em_disk='1'; /*-将该空闲块设置为已分配-*//*-------------填写目录项----------*/strcpy(cur_dir->directitem[i].nam e,name);cur_dir->directitem[i].firstdisk=j ;cur_dir->directitem[i].size=ROOT _DISK_SIZE;cur_dir->directitem[i].next=j;cur_dir->directitem[i].property=' 1';/*-所创目录在虚拟磁盘上的地址(内存物理地址)-*/cur_mkdir=(struct direct *)(fdisk+cur_dir->directitem[i].firstdisk*D ISKSIZE);/*-初始化目录-*//*-指向当前目录的目录项-*/cur_mkdir->directitem[0].sign=0 ;cur_mkdir->directitem[0].firstdis k=cur_dir->directitem[i].firstdisk;strcpy(cur_mkdir->directitem[0]. name,".");cur_mkdir->directitem[0].next=c ur_mkdir->directitem[0].firstdisk;cur_mkdir->directitem[0].proper ty='1';cur_mkdir->directitem[0].size=R OOT_DISK_SIZE;页脚内容20/*-指向上一级目录的目录项-*/cur_mkdir->directitem[1].sign=c ur_dir->directitem[0].sign;cur_mkdir->directitem[1].firstdis k=cur_dir->directitem[0].firstdisk;strcpy(cur_mkdir->directitem[1]. name,"..");cur_mkdir->directitem[1].next=c ur_mkdir->directitem[1].firstdisk;cur_mkdir->directitem[1].propert y='1';cur_mkdir->directitem[1].size=R OOT_DISK_SIZE;for(i=2;i<MSD+2;i++) /*-子目录都初始化为空-*/{cur_mkdir->directitem[i].sign=0;cur_mkdir->directitem[i].firstdisk=-1;strcpy(cur_mkdir->directitem[i].name ,"");cur_mkdir->directitem[i].next=-1;cur_mkdir->directitem[i].property='0 ';cur_mkdir->directitem[i].size=0;}return 0;}int rmdir(char *name){int i,j,item;struct direct *temp_dir;页脚内容21/*-检查当前目录项中有无该目录-*/for(i=2;i<MSD+2;i++){if(!strcmp(cur_dir->directitem[i].nam e,name))break;}if(i>=MSD+2) /*-没有这个文件或目录-*/return(-1);if(cur_dir->directitem[i].property !='1')/*-删除的不是目录-*/return(-3);/*-判断要删除的目录有无子目录-*/temp_dir=(struct direct *)(fdisk+cur_dir->directitem[i].next*DISK SIZE);for(j=2;j<MSD+2;j++){if(temp_dir->directitem[j].next!=-1)break;}if(j<MSD+2) /*-有子目录或文件-*/return(-2);/*------------找到起始盘块号,并将其释放----------------*/item=cur_dir->directitem[i].first disk;fat[item].em_disk='0';/*-修改目录项-*/cur_dir->directitem[i].sign=0;cur_dir->directitem[i].firstdisk=-页脚内容221;strcpy(cur_dir->directitem[i].nam e,"");cur_dir->directitem[i].next=-1;cur_dir->directitem[i].property=' 0';cur_dir->directitem[i].size=0;return 0;}void dir(){int i;for(i=2;i<MSD+2;i++){if(cur_dir->directitem[i].firstdisk!=-1) /*-如果存在子目录-*/{printf("%s\t",cur_dir->directitem[i].n ame);if(cur_dir->directitem[i].property==' 0') /*-文件-*/printf("%d\t\t\n",cur_dir->directite m[i].size);elseprintf("\t<目录>\t\n");}}}int cd(char *name){int i,j,item;页脚内容23char *str;char *temp,*point,*point1;struct direct *temp_dir;temp_dir=cur_dir;str=name;if(!strcmp("\\",name)){cur_dir = root;strcpy(bufferdir,"Root:");return 0;}temp = (char *)malloc(DIR_MAXSIZE*sizeof(char));/*-最长路径名字分配空间-*/for(i=0;i<(int)strlen(str);i++)temp[i]=str[i];temp[i]='\0';for(j=0;j<MSD+2;j++) /*-查找该子目录是否在当前目录中-*/{if(!strcmp(temp_dir->directitem[j].na me,temp))break;}free(temp);/*释放申请的临时空间*///if(temp_dir->directitem[j].pro perty!='1') /*-打开的不是目录-*///return(-2);if(j>=MSD+2) /*-不在当前目录-*/return(-1);页脚内容24item=temp_dir->directitem[j].fir stdisk;/*-当前目录在磁盘中位置-*/temp_dir=(struct direct *)(fdisk+item*DISKSIZE);if(!strcmp("..",name)){if(cur_dir->directitem[j-1].sign!=1)/*-如果上级目录不是根目录-*/{point=strchr(bufferdir,'\\'); //查找字符串bufferdir中首次出现字符\ 的位置while(point!=NULL){point1=point+1;/*-减去'\'所占的空间,记录下次查找的起始地址-*/point=strchr(point1,'\\');}*(point1-1)='\0'; /*-将上一级目录删除-*/}}else{//if(name[0] !='\\')bufferdir = strcat(bufferdir,"\\"); /*-修改当前目录-*/bufferdir = strcat(bufferdir,name);页脚内容25}cur_dir=temp_dir; /*-将当前目录确定下来-*/return 0;}void show(){printf("%s>",bufferdir);}void print(){printf("******************** ******************************** *****\n");printf("******************** **文件系统设计***********************\n");printf("*\t命令格式说明*\n");printf("*\tcd 目录名更改当前目录*\n");printf("*\tmkdir 目录名创建子目录*\n");printf("*\trmdir 目录名删除子目录*\n");printf("*\tdir 显示当前目录的子目录*\n");printf("*\tcreate 文件名创建文件*\n");printf("*\tdel 文件名删除文件*\n");printf("*\topen 文件名打开文件*\n");printf("*\tclose 文件名关闭文件*\n");printf("*\tread 读文件*\n");页脚内容26printf("*\twrite 写文件*\n");printf("*\texit 退出系统*\n");printf("******************** ******************************** *****\n");}void main(){FILE *fp;char ch;char a[100];char code[11][10];char name[10];int i,flag,r_size;char *contect;contect = (char *)malloc(MAX_WRITE*sizeof(char));if((fp=fopen("disk.dat","rb"))= =NULL){printf("You have not format,Do you want format?(y/n)");scanf("%c",&ch);if(ch=='y'){initfile();printf("Successfully format! \n");}else{页脚内容27return;}}enter();print();show();strcpy(code[0],"exit"); strcpy(code[1],"create");strcpy(code[2],"open");strcpy(code[3],"close");strcpy(code[4],"write");strcpy(code[5],"read");strcpy(code[6],"del");strcpy(code[7],"mkdir");strcpy(code[8],"rmdir");strcpy(code[9],"dir");strcpy(code[10],"cd");while(1){scanf("%s",a);for(i=0;i<11;i++){if(!strcmp(code[i],a))break;}switch(i){case 0: //退出文件系统free(contect);halt();return;case 1: //创建文件页脚内容28scanf("%s",name);flag = create(name);if(flag==-1){printf("Error: \n The length is too long !\n");}else if(flag==-2){printf("Error: \n The direct item is already full !\n");}else if(flag==-3){printf("Error: \n The number of openfile is too much !\n");}else if(flag==-4){printf("Error: \n The name is already in the direct !\n");}else if(flag==-5){printf("Error: \n The disk space is full!\n");}else{printf("Successfully create a file! \n");}show();break;case 2://打开文件页脚内容29scanf("%s",name);fd = open(name);if(fd == -1){printf("Error: \n The open file not exit! \n");}else if(fd == -2){printf("Error: \n The file have already opened! \n");}else if(fd == -3){printf("Error: \n The number of open file is too much! \n");}else if(fd == -4){printf("Error: \n It is a direct,can not open for read or write! \n");}else{printf("Successfully opened! \n");}show();break;case 3://关闭文件scanf("%s",name);flag = close(name);if(flag == -1){页脚内容30printf("Error:\n The file is not opened ! \n");}else{printf("Successfully closed! \n");}show();break;case 4://写文件if(fd ==-1){printf("Error:\n The file is not opened ! \n");}else{printf("Please input the file contect:");scanf("%s",contect);flag=write(fd,contect,strlen(contect));if(flag == 0){printf("Successfully write! \n");}else{printf("Error:\n The disk size is not enough! \n");}}页脚内容31show();break;case 5://读文件if(fd ==-1){printf("Error:\n The file is not opened ! \n");}else{flag = read(fd,contect);if(flag == 0){for(i=0;i<u_opentable.openitem[fd].s ize;i++){printf("%c",contect[i]);}printf("\t\n");}}show();break;case 6://删除文件scanf("%s",name);flag = del(name);if(flag == -1){printf("Error:\n The file not exit! \n");}else if(flag == -2)页脚内容32{printf("Error:\n The file is opened,please first close it ! \n");}else if(flag == -3){printf("Error:\n The delete is not file ! \n");}else{printf("Successfully delete! \n");}show();break;case 7://创建子目录scanf("%s",name);flag = mkdir(name);if(flag == -1){printf("Error:\n The length of name is to long! \n");}else if(flag == -2){printf("Error:\n The direct item is already full ! \n");}else if(flag == -3){printf("Error:\n The name is already in the direct ! \n");}else if(flag == -4)页脚内容33{printf("Error: \n '..' or '.' can not as the name of the direct!\n");}else if(flag == -5){printf("Error: \n The disk space is full!\n");}else if(flag == 0){printf("Successfully make dircet! \n");}show();break;case 8://删除子目录scanf("%s",name);flag = rmdir(name);if(flag == -1){printf("Error:\n The direct is not exist! \n");}else if(flag == -2){printf("Error:\nThe direct has son direct ,please first remove the son dircct!\n");}else if(flag == -3){printf("Error:\n The remove is not direct ! \n");}页脚内容34else if(flag == 0){printf("Successfully remove dircet! \n");}show();break;case 9://显示当前子目录dir();show();break;case 10://更改当前目录scanf("%s",name);flag = cd(name);if(flag == -1){printf("Error:\n The path no correct!\n");}else if(flag == -2){printf("Error:\nThe opened is not direct!\n");}show();break;default:printf("\n Error!\n The command is wrong! \n");show();}}页脚内容35}5.程序运行截图6.实验总结页脚内容36通过这一次计算机操作系统的上机实验，使我对不同环境下的操作系统有了进一步的了解，使我学到了很多关于Linux的操作和相关知识。