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UNIX signal problem

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# 1  
Old 03-06-2011
UNIX signal problem
Hi all,
Sorry about the title,at first i decided to ask a problem about the signal mechanism,however,i'm now figured it out.Sorry to forget modify the titleSmilie.I had a small problem that if i use the code which is commented,the code would get a segment fault,while the above code NOT.what's the problem?
Code:
void sig_handler(int signo)
{
	printf("signo = %d\n",signo);
}

int main()
{	
	struct sigaction sa;
	pid_t pid;

	sa.sa_handler = sig_handler;
	
	if(sigaction(SIGUSR1,&sa,NULL) < 0){
		perror("sigaction failed");
		exit(1);
	}

	printf("my pid is %d\n",getpid());

	sigset_t set;
	sigemptyset(&set);

	int i = sigsuspend(&set);
	//sigsuspend(&set);
	return 0;	
}

# 2  
Old 03-06-2011
So, what are the contents of your "struct sigaction sa" when you make the call to sigaction()?
This User Gave Thanks to achenle For This Post:
homeboy
# 3  
Old 03-06-2011
Quote:
Originally Posted by achenle
So, what are the contents of your "struct sigaction sa" when you make the call to sigaction()?
sorry,I don't get your point.you means this?
Code:
sa.sa_handler = sig_handler;

I did set the handler.....
# 4  
Old 03-07-2011
and left the remaining 99% of the structure as garbage, looks like. See 'man sigaction', most of them are important.
This User Gave Thanks to Corona688 For This Post:
homeboy
# 5  
Old 03-07-2011
Thanks to all,my initialization is uncompleted.Now it's ok by added :
Code:
 sigemptyset(&sa.sa_mask);
 sa.sa_flags = 0;

This User Gave Thanks to homeboy For This Post:
Corona688
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