[완료] 터미널에서 아무 입력이나 발생시 발생하는 시그널이 있나요?

#include <stdio.h>
#include <stdlib.h>
#include <sys/time.h>
#include <sys/types.h>
#include <string.h>
#include <unistd.h>
 
int main(void)
{
	fd_set rfds;
	struct timeval tv;
	int retval;
	FILE *fp = stdin;
	int fd = fileno(fp);
	char buf[BUFSIZ];
 
	while (1)
	{
		/* Watch stdin (fd 0) to see when it has input. */
		FD_ZERO(&rfds);
		FD_SET(fd, &rfds);
 
		/* Wait up to one second. */
		tv.tv_sec = 1;
		tv.tv_usec = 0;
 
		retval = select(fd+1, &rfds, NULL, NULL, &tv);
		/* Don’t rely on the value of tv now! */
		if (retval == -1)
		{
			perror("select()");
			return EXIT_FAILURE;
		}
		else if (retval == 0)
		{
			printf("No data within one second.\n");
			continue;
		}
 
		/* Data is available now. */
		if (FD_ISSET(fd, &rfds))
		{
			fgets(buf, sizeof(buf), fp);
 
			/* Parse input command. */
			if (!strncmp(buf, "quit", strlen("quit")))
				/* stop busy work */
				break;
			else
				printf(" > %s", buf);
		}
	}
 
	exit(EXIT_SUCCESS);
}