text10~1.txt

Linux下的C语言编程

#include <stdio.h>
#include <signal.h>
#include <stdarg.h>
#include <sys/time.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>

int my_printf(const char *fmt,...);
void sighandler(int signum);
void continuehandler(int signumber);
char buffer[200];

int main(void)
{
    	struct itimerval itimer;
    	sigset_t blockset,pending;
    	int pendingcount;
	
    	strcpy(buffer,"None\n");

    	if(signal(SIGINT,&sighandler)==SIG_ERR)
    	{
        	my_printf("Couldn’t register signal handler for SIGINT. \n");
    	}

    	if(signal(SIGTERM,&sighandler)==SIG_ERR)
    	{
        	my_printf("Couldn’t register signal handler for SIGTERM. \n");
    	}

    	if(signal(SIGCONT,&sighandler)==SIG_ERR)
    	{
        	my_printf("Couldn’t register signal handler for SIGCONT. \n");
    	}

     	sigemptyset(&blockset);
     	sigaddset(&blockset, SIGINT);
     	sigaddset(&blockset, SIGTERM);
     
    	itimer.it_interval.tv_usec=0; 
    	itimer.it_interval.tv_sec=0;

    	itimer.it_value.tv_usec=0; 
    	itimer.it_value.tv_sec=0;

    	for(  ;  ;  )
    	{
        	sigprocmask(SIG_BLOCK,&blockset, NULL);
        	alarm(15);
        	fgets(buffer,sizeof(buffer),stdin);
        	my_printf("input: %s",buffer);
       
        	sigpending(&pending);
        	pendingcount=0;
        	if(sigismember(&pending, SIGINT))
			pendingcount++;
        	if(sigismember(&pending, SIGTERM))
			pendingcount++;
        	if(pendingcount)
        	{
            		my_printf("There are %d signals. \n",pendingcount);
        	}

        	sigprocmask(SIG_UNBLOCK,&blockset,NULL);

        	if(strcmp(buffer,"exit\n")==0)
        	{
             		raise(SIGKILL);
        	}
    	}
    	return 0;
}


int my_printf(const char *fmt,...)
{
    	va_list args;
    	struct tm *tstruct;
    	time_t tsec;
    
    	tsec=time(NULL);
    	tstruct=localtime(&tsec);
    
    	my_printf("%02d:%02d:%02d %05d|",
	tstruct->tm_hour,
	tstruct->tm_min,
	tstruct->tm_sec,
	getpid());

	va_start(args, fmt);
	return vprintf(fmt,args);
}


void sighandler(int signumber)
{
    	my_printf("Caught sight %d. \n",signumber);
}


void continuehandler(int signumber)
{
    	my_printf("Continuint. \n");
    	my_printf("Your last input was: %s", buffer);
}


void alarmhandler(int signumber)
{
    	my_printf("No activity for 15 seconds, exiting. \n");
    	exit(0);
}