parent process behaviour to signal after vfork()

From: Halesh S
Date: Tue Oct 28 2008 - 02:43:47 EST


Hi,

Please find the below test code...

#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <unistd.h>
int x = 0;
typedef void (*sighandler_t)(int);
void fun()
{
printf("SIGNAL CAUGHT\n");
}

int main()
{
int pid;

signal(SIGINT, (sighandler_t)fun);
signal(SIGSEGV, (sighandler_t)fun);
pid = vfork();

if ( pid == 0 ) {
printf(" I am child - %d \n", pid);
x++;
raise(SIGINT);
printf("x = %d\n", x);
exit(0);
}
else {
printf(" I am parent - %d\n", pid);
raise(SIGSEGV);
printf("x = %d\n", x);
}
}

Why the parent process is not able to handle/respond the signals, when a child
once handles the signal, child is created using vfork().

In vfork() man page -
"Signals to the parent arrive after the child releases the parent's
memory."

How to make sure that child has released the parent memory..??

Thanks,
Halesh










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