test10_5.txt

Linux下的C语言编程

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

#if defined(__Linux__)&&! defined(SI_KERNEL)
#define SI_KERNEL 0x80
#endif

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

int main(void)
{
    	struct sigaction act;
    	sigset_t blockset, pending;
    	int pendingcount;

	strcpy(buffer, "None\n");

	sigemptyset(&blockset);
	act.sa_mask=blockset;
	act.sa_flags=SA_SIGINFO;
	act.sa_sigaction=&sighandler;
	if(sigaction(SIGTERM,&act,NULL)==-1)
	{
        	my_printf("Couldn’t register signal for SIGINT.\n");
    	}
    	act.sa_sigaction=&continuehandler;
    	if(sigaction(SIGCONT,&act,NULL)==-1)
    	{
        	my_printf("Couldn’t register signal for SIGCONT.\n");
    	}
    	sigaddset(&blockset,SIGTERM);
    	sigaddset(&blockset,SIGINT);

    	for(  ;  ;  )
    	{
        	sigprocmask(SIG_BLOCK,&blockset,NULL);
        	fgets(buffer,sizeof(buffer),stdin);
        	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 pending.\n",pendingcount);
         	}

         	sigprocmask(SIG_UNBLOCK,&blockset,NULL);
    	}
    	return 0;
}

int my_printf(const char *fmt,...)
{
   	va_list args;
    	struct tm *tstruct;
    	time_t tsec;
    
    	tsec=time(NULL);
    	tstruct=localtime(&tsec);
    
    	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,siginfo_t *info,void *extra)
{
    	my_printf("Caught signal %d from",signumber);
    	switch(info->si_code)
    	{
        	case SI_USER: printf("a user process \n");
                     	break;
        	case SI_KERNEL: printf("the kernel \n");
                       	break;
        	default: printf("something,strange \n");
    	}
}

void continuehandler(int signumber,siginfo_t *info,void *estra)
{
    	my_printf("Continuing. \n");
    	my_printf("Your last input was: %s",buffer);
}