Question

我一直在尝试使用信号在C中开发3人游戏，但它没有提供所需的输出。

#define _POSIX_SOURCE   //to use functionality from the POSIX.1 standard as ANCI C does not support kill()
#include <sys/wait.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <signal.h>
#include <fcntl.h>
#include <time.h>

void action(){}
void child(char *);

int main(){
  pid_t pid1, pid2, pid3;

  printf("This is a 3-players game with a referee\n\n");
  if((pid1=fork()) == 0) child("TOTO");
  sleep(1);
  if((pid2=fork()) == 0) child("TITI");
  sleep(1);
  if((pid3=fork()) == 0) child("TUTU");

  sleep(1);
 while(1){
    signal(SIGUSR1, action);
    printf("Refree: TOTO plays\n\n");
    kill(pid1, SIGUSR1);
    pause();
    printf("Refree: TITI plays\n\n");
    kill(pid2, SIGUSR1);
    pause();
    printf("Refree: TUTU plays\n\n");
    kill(pid3, SIGUSR1);
    pause();
  }
}
void child(char *s){
  int points=0, dice;
  srand(time(NULL));

  while(1){
    signal(SIGUSR1, action);  // block myself
    pause();
    sleep(1);
    printf("%s: playing my dice\n", s);
    dice = rand() % 10 + 1;
    printf("%s: got %d points\n", s, dice);
    points+=dice;
    printf("%s: Total so far %d\n\n", s, points);
    sleep(3);
    if(points >= 100){
      printf("%s: game over I won\n", s);
      kill(0, SIGTERM);
    }
    kill(getppid(), SIGUSR1);
  } 
}

我得到的输出是：

This is a 3-players game with a referee

Refree: TOTO plays

TOTO: playing my dice
TOTO: got 8 points
TOTO: Total so far 8

Refree: TITI plays

TITI: playing my dice
TITI: got 2 points
TITI: Total so far 2

User defined signal 1

它永远不会显示＆＃34; TUTU＆＃34;玩骰子并使用注册为空白信号的用户定义信号1终止。该程序应在玩家获胜后终止。

有什么建议吗？

Answer 1

当裁判收到TOTO的信号时，它的处置会重置为SIG_DFL，因此TITI的信号确实会杀死他。在每个signal(SIGUSR1, action)之前，裁判必须每个循环调用kill()三次。

另一种选择是#define _BSD_SOURCE（仔细阅读man 2 signal的可移植性部分），它强加了不重置处置的BSD语义

使用信号在C中的3人游戏

1 个答案: