进程通信

#include "conio.h"                          
#include "stdio.h"
#include "stdlib.h"              
struct jincheng_type
   { 
     int pid;
     int youxian;
     int daxiao;
     int msg;
     int live;
     };

    struct jincheng_type neicun[20],waicun[20];
    int shumu=0,pid_l;
    main()
  {
    int n,m,i;
    char a;
    n=1;
    while(n==1)
      {
	system("cls");
	printf("\n********************************************");
	printf("\n*                进程演示系统              *");
	printf("\n********************************************");
	printf("\n     1.创建新的进程     2.查看运行进程 ");
	printf("\n     3.换出某个进程     4.杀死运行进程 ");
	printf("\n     5.进程之间通信     6.退出               ");
	printf("\n********************************************");
	printf("\n请选择（1～6) ");
	a=getch();


        switch(a)
	{ 
         case'1':
	 create( );
	 break;
	 case'2':
	 viewrun( );
	 break;
	 case'3':
	 huanchu();
	 break;
	 case'4':
	 kill( );
	 break;
	 case'5':
	 tongxun( );
	 break;
	 case'6': exit(0);
	 default: n=0;
	  }
      }
  }

          create( )  /* 创建一个进程的示例（不完整的程序） */
{
	   if(shumu>=20)
                {
	          printf("\n内存已满，请先结束或换出进程\n");
                }
              else
                 {
		   printf("\n请输入新进程的pid\n");
	           scanf("%d",&neicun[shumu+1].pid);
	           printf("\n请输入新进程的优先级\n");
	           scanf("%d",&neicun[shumu+1].youxian);
	           printf("\n请输入新进程的大小\n");
	           scanf("%d",&neicun[shumu+1].daxiao);
	           printf("\n请输入新进程的消息\n");
	           scanf("%d",&neicun[shumu+1].msg);
	           neicun[shumu+1].live=1;
	           shumu++;
                 }
                 return neicun[shumu-1].live;
}
           viewrun( )/*查看运行进程*/
           {         
	   int vpid;
           printf("\n请输入进程的pid\n");
           scanf("%d",&vpid);  

	   if(vpid>0&&vpid<=20&&neicun[vpid].live==1)
	     {
	     	printf("\n进程的pid是: %d\n",neicun[vpid].pid);
		printf("进程的优先级是: %d\n",neicun[vpid].youxian);
		printf("进程的大小是:%d\n",neicun[vpid].daxiao);
		printf("进程的消息是:%d\n",neicun[vpid].msg);
		     }
            else
              {
		printf("\n所查看运行进程不存在\n");
              }
	        printf("请按回车退出查看\n");
	        vpid=getch();
                }
                huanchu()/*换出某个进程*/
                { 
                int pid1,pid2;
	        char c;
                printf("\n请输入第一个替换进程的pid\n");
                scanf("%d",&pid1);
                printf("\n请输入第二个替换进程的pid\n");
                scanf("%d",&pid2);
	        if(pid1>0&&pid1<=20&&neicun[pid1].live==1)
               {
                if(neicun[pid1].youxian>neicun[pid2].youxian)
              	{
              	  waicun[20].pid=neicun[pid1].pid;
              	  waicun[20].youxian=neicun[pid1].youxian;
              	  waicun[20].daxiao=neicun[pid1].daxiao;
              	  waicun[20].msg=neicun[pid1].msg;

		  neicun[pid1].pid=neicun[pid2].pid;
              	  neicun[pid1].youxian=neicun[pid2].youxian;
              	  neicun[pid1].daxiao=neicun[pid2].daxiao;
              	  neicun[pid1].msg=neicun[pid2].msg;
              	  
		  neicun[pid2].pid=waicun[20].pid;
		  neicun[pid2].youxian=waicun[20].youxian;
		  neicun[pid2].daxiao=waicun[20].daxiao;
		  neicun[pid2].msg=waicun[20].msg;

		  printf("\n替换完成\n");
		  printf("\n被替换进程的pid是: %d\n",waicun[20].pid);
		  printf("被替换进程的优先级是: %d\n",waicun[20].youxian);
		  printf("被替换进程的大小是:%d\n",waicun[20].daxiao);
		  printf("被替换进程的消息是:%d\n",waicun[20].msg);
		  }
		  else
		  {
		  printf("\n进程优先级不够大");
		  }
                  }
                  else
                  {
                  printf("所查看运行进程不存在");
	          }
	          printf("请按回车退出换出进程\n");
	          c=getche();
	          return;
                  }
                  kill()/*杀死运行进程*/
                 { 
    
	          int kpid;
	          printf("\n请输入进程的pid\n");
                  scanf("%d",&kpid);
	          if(kpid>0&&kpid<20&&neicun[kpid].live==1)
                 {
		  neicun[kpid].live=0;
                  }
                  return;
                  }
                  tongxun( )/*进程之间通信*/
                  {
                  int tpid1,tpid2;
                  int buffer;
                  char d;
	          printf("\n请输入通信源进程pid\n");
                  scanf("%d",&tpid1);
                  printf("\n请输入通信目的进程pid\n");
                  scanf("%d",&tpid2);
	          if(tpid1>0&&tpid1<20&&neicun[tpid1].live==1)
              {
              	buffer=neicun[tpid1].msg;
              	neicun[tpid1].msg=neicun[tpid2].msg;
              	neicun[tpid2].msg=buffer;		
		printf("\n源进程的消息是: %d\n",neicun[tpid1].msg);
		printf("\n目的进程的消息是: %d\n",neicun[tpid2].msg);
              }
                  else
              {
              printf("\n所查看运行进程不存在\n");
	      }
	      printf("\n请按回车退出进程通信\n");
              d=getch();
              return;
}