fasynctest.c

来自「盛博can驱动程序功能很全」· C语言 代码 · 共 42 行

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


int input_handler(void)
{
 printf("message come!\n");
 return 0;
} 

int main(void)
{
 int fd;
 int result;

signal(SIGIO,&input_handler); 

fd=open("/dev/can0",O_RDWR);
if (fd<0)
    printf("open failed\n");
 
fcntl(fd,F_SETOWN,getpid());
fcntl(fd,F_SETFL, FASYNC|fcntl(fd,F_GETFL));

while (1) {
 /*
  here you can do your other job ,such as analyse the data ,send answer message
  etc, especially for the process which need much time,you can process it while
  no data come.if data came ,the input_handler will receive it in buf automatic 
  and needn't  you wait the data comming.
*/ 
}

 if (close(fd)) 
   printf("close failed\n"); 

return 1;
}