学步园

psched.c文件

#include <stdio.h> 
#include <stdlib.h> 
#include <sched.h> 
#include <sys/time.h> 
#include <sys/resource.h>
#include <signal.h> 

typedef void (*sighandler_t)(int);
   void sigcat(){
//实现优先数+1
   setpriority(PRIO_PROCESS,getpid(), getpriority(PRIO_PROCESS,0)+1);
   }
   void sigzat(){
//实现优先数-1
   setpriority(PRIO_PROCESS,getpid(), getpriority(PRIO_PROCESS,0)-1);
   }
   void nothing() {}  
   int main(int argc, char *argv[]) 
{ 
     int i,j,status; 
     int pid; //存放进程号
     struct sched_param p[2]; //设置调度策略时使用的数据结构
     //SIGINT对应sigcat，SIGTSTP对应sigzat
     if((pid=fork()) <0){ 
      perror("process not create"); 
      exit(EXIT_FAILURE); 
      }
     else if(pid>0){
      signal(SIGINT, (sighandler_t)sigcat);
      signal(SIGTSTP, (sighandler_t)nothing);
      sched_setscheduler(getpid(), SCHED_OTHER, &p[0]);
      setpriority(PRIO_PROCESS, getpid(), 0);
      sleep(1); //每隔1妙报告一次进程号和优先级 
      for(i=0; i<10; i++){ 
          printf("Parent PID = %d priority = %d\n",getpid(),getpriority(PRIO_PROCESS,0)); 
          printf("按Ctrl+c可为父进程的优先数加1\n");
          pause();
          sleep(1);
      }
        exit( EXIT_SUCCESS); 
     }
     //各子进程循环报告其优先数和调度策略 
     else{ 
      sleep(1); //每隔1妙报告一次进程号和优先级
      signal(SIGTSTP, (sighandler_t)sigzat);
      signal(SIGINT, (sighandler_t)nothing);
      sched_setscheduler(getpid(), SCHED_OTHER, &p[1]);
      setpriority(PRIO_PROCESS, getpid(), 0);
      sleep(1); //每隔1妙报告一次进程号和优先级 
      for(i=0; i<10; i++){ 
          printf("Child PID = %d priority = %d\n",getpid(),getpriority(PRIO_PROCESS,0)); 
          printf("按Ctrl+z可为父进程的优先数加1\n");
          pause();
          sleep(1);
      }
      exit( EXIT_SUCCESS); 
     }
      return EXIT_SUCCESS;
}

MakeFile文件：

srcs = psched.c 

objs = psched.o

opts = -g -c 

all:  psched 

psched:  $(objs) 

gcc $(objs) -o psched 

psched.o:  $(srcs) 

gcc $(opts) $(srcs) 

clean: 

rm psched *.o