compile C and execute "python t.py", press CTRL+C or CTRL+\ when executing python. will print "^Cgot signal" in my laptop

t.c

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <signal.h>

int signaled = 0;

void handler(int ignored) {
	signaled = 1;
}

int main() {
	if (signal(SIGINT, handler) == SIG_ERR)
		return 1;

	if (sleep(10) == 0)
		printf("no signal\n");
	else
		printf("got signal\n");

	return 0;
}

t.py

#!/usr/bin/env python

import os

def main():
	try:
		os.system("./a.out");
	except KeyboardInterrupt as e:
		print "got signal in os.system"

if __name__ == '__main__':
	main()