时钟控制字符串输出 

  1 /*
  2     时钟控制字符串输出
  3     **world*hello**apue******
  4 */
  5 #include <stdio.h>
  6 #include <stdlib.h>
  7 #include <signal.h>
  8 #include <string.h>
  9 #include <sys/time.h>
 10 #include <unistd.h>
 11 #include <errno.h>
 12 
 13 #define MAXALARM 1024
 14 
 15 typedef struct {  //显示字符串
 16     int sec;
 17     void (*handler)(void *s);
 18     char s[20];
 19 }ar;
 20 
 21 static ar *arr[MAXALARM];
 22 static int inited;
 23 
 24 static int get_pos(void)
 25 {
 26     for(int i = 0; i < MAXALARM; i++)
 27     {
 28         if(arr[i] == NULL)
 29         {
 30             return i;
 31         }
 32     }
 33 }
 34 
 35 static void print(int i)//打印数组成员
 36 {    
 37     (arr[i]->handler)(arr[i]->s);
 38     arr[i] = NULL;
 39     free(arr[i]);
 40 }
 41 
 42 static void handleri(int s)
 43 {
 44     for(int i = 0; i < MAXALARM; i++)
 45     {
 46         if(arr[i] != NULL)
 47         {
 48             arr[i]->sec -= 1;
 49             if(arr[i]->sec == 0)
 50         print(i);
 51         }
 52     } 
 53 }
 54 
 55 static void statdo(void)//定义时钟
 56 {
 57     struct sigaction act, oldact;
 58     struct itimerval itv, olditv;
 59 
 60     act.sa_handler = handleri;
 61     act.sa_flags = 0;
 62     sigemptyset(&act.sa_mask);
 63     sigaction(SIGALRM, &act, &oldact);
 64 
 65     itv.it_interval.tv_sec = 1;
 66     itv.it_interval.tv_usec = 0;
 67     itv.it_value.tv_sec = 1;
 68     itv.it_value.tv_usec = 0;
 69     setitimer(ITIMER_REAL, &itv, &olditv);
 70 
 71 }
 72 
 73 void anytimer_alarm(int sec, void (*handler)(void *s), char *p)
 74 {
 75     ar *t = NULL;
 76     int pos;
 77 
 78     
 79     if(!inited)
 80     {
 81         statdo();
 82         inited = 1;
 83     }
 84     
 85     t = malloc(sizeof(ar));
 86     if(NULL == t)
 87         return ;
 88 
 89     t->sec = sec;
 90     t->handler = handler;
 91     strcpy(t->s,p);
 92 
 93     pos = get_pos();
 94     if(pos < 0)
 95     {
 96         free(t);
 97         return ;
 98     }
 99 
100     arr[pos] = t;
101 }
102 
103 static void any1(void *s)
104 {
105     printf("%s", (char *)s);
106     fflush(NULL);
107 }
108 
109 static void any2(void *s)
110 {
111     printf("%s", (char *)s);
112     fflush(NULL);
113 }
114 
115 static void any3(void *s)
116 {
117     printf("%s", (char *)s);
118     fflush(NULL);
119 }
120 
121 int main(void)
122 {
123     anytimer_alarm(3, any1, "hello");
124     anytimer_alarm(2, any2, "world");
125     anytimer_alarm(5, any3, "apue");
126 
127     /*
128      **world*hello**apue******
129      */
130     while (1) {
131         write(1, "*", 1);
132         sleep(1);
133     }
134 
135     return 0;
136 }

 

posted @ 2019-03-24 22:03  乐小童  阅读(230)  评论(0)    收藏  举报