sigaction() doesn't catch SIGINT signal - c

Question

I am currently learning about signals in C and have a small program, that is supposed to not terminate upon receiving the SIGINT signal using sigaction().
The code written below however does terminate, even though it looks fine to me. Maybe I am something missing. Does someone see, why it still terminates?
#include <signal.h>
#include <stdio.h>
#include <unistd.h>
void handle() { printf("%s%d%s", "I won't die....: ", getpid(), "\n"); }
int main() {
struct sigaction sa;
sa.sa_handler = handle;
int k = 0;
sigaction(SIGINT, &sa, NULL);
// signal(SIGINT, handle); //signal works just fine
while (k < 60) {
printf("%s", "sleeping... \n");
sleep(1);
k = k + 1;
}
}
Additional info: My OS is Windows, however I compile and execute the program in the Bash of a Linux subsystem.

Answer 1

Open the manual page of sigaction() and understand all the members of struct sigaction and fill all the members of struct sigaction.
struct sigaction {
void (*sa_handler)(int);
void (*sa_sigaction)(int, siginfo_t *, void *);
sigset_t sa_mask;
int sa_flags;
void (*sa_restorer)(void);
};
Here
struct sigaction sa;
As pointed by #AnttiHaapala here sa is a variable of automatic storage duration and you didn't initialize its members, it invokes undefined behavior as all the other fields contain garbage except sa.sa_handler
So you need to fill the other members of struct sigaction like
sa.sa_handler = handle;
sa.sa_flags = 0;
sigemptyset(&sa.sa_mask);
Or initialize sa itself like
struct sigaction sa = {0};
Also it's not a good practice to write printf() statement inside signal handler, read here How to avoid using printf in a signal handler? .