proc_usr.c

实现模块的加载等实现。在LINUX操作系统下实现 操作系统实验程序之一

#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

#define size 2048

void inform()
{
     printf("you can do these things:\n");
     printf("press 1 :insert a student;\n");
     printf("press 2 :delete a student;\n");
     printf("press 3 :to read all of students' information;\n");
     printf("press 4 :exit system;\n");
}

int main()
{
    int command;
    char *filename="/proc/proc_text/student";
    char name[10];
    char id[10];
    char buf[25];
    char inbuf[size];
    int numbytes;
    int fpw,fpr;

    inform();//打印菜单

    scanf("%d",&command);//读命令号
    while(command!=4)//若未选择退出则循环
         {
           switch(command)
              {
                 case 1://若为插入
                     printf("input student'name,than press enter:\n");
                     scanf("%s",name);//读姓名
                     char ch=getchar();//姓名后的回车
                     printf("input student'id,than press enter:\n");
                     scanf("%s",id);//读学号
                     ch=getchar();//学好后的回车
                     strcpy(buf,"insert-");//以“命令号－姓名－学号”的形式存入缓冲区，传给核心态
                     strcat(buf,name);
                     strcat(buf,"-");
                     strcat(buf,id);

                     fpw=open(filename,O_WRONLY);
                     write(fpw,buf,strlen(buf));//调用写函数
                     printf("ok\n");//返回成功
                     close(fpw);
                     break;

                 case 2://若为删除
                     printf("input student'name,than press enter:\n");
                     scanf("%s",name);
                     char ch2=getchar();
                     printf("input student'id,than press enter:\n"); 
                     scanf("%s",id);
                     ch2=getchar();
                     strcpy(buf,"delete-");
                     strcat(buf,name);
                     strcat(buf,"-");
                     strcat(buf,id);

                     fpw=open(filename,O_WRONLY);
                     write(fpw,buf,strlen(buf));
                     printf("ok\n");
                     close(fpw);
                     break;
              
                 case 3://若为读
                     fpr=open(filename,O_RDONLY);
                     numbytes=read(fpr,inbuf,size);
                     inbuf[numbytes]='\0';
                     printf("%s\n",inbuf);
                     close(fpr);

                 case 4://若退出
                     break;

                 default://其它命令号显示错误
                     printf("error\n");
               }
            
            inform();//为下一选择打印命令号菜单
            scanf("%d",&command);//读入下一命令号
   
         }

     return 0;
}