Unis signal handling in parent child scenario.

gnutuxy_at_yahoo.co.in
Date: 09/30/04 

Date: 29 Sep 2004 22:47:15 -0700

Hi,

I am newbie in the Unix system programming and in learning phase.
I usually read the libc manual and then try to implement small
programs to test/check the learnt thing.

I read the libc manual for signals and tried the program to check
whether child
inherits the signal handler intalled by parent befor fork.

I am totally confused about it because the code won't work as per the
the manual. Manual says child inherits signal action and signal mask.

My situation is as follows:
Question : Why I won't get message "Received the signal: #" on the
terminal, when I signaled child process with SIGINT?

==================glibc manual extract==============
 * The set of pending signals (*note Delivery of Signal::) for the
   child process is cleared. (The child process inherits its mask of
   blocked signals and signal actions from the parent process.)
====================================================

My try : I just want to check that the signal handler installed in
Parent is
         inherited by child ( this is what I interpreted from the
glibc manual,
         the extract of the manual is highlighted above. )

Here is my code.
=================my code============================
#include <stdio.h>
#include <signal.h>
#include <unistd.h>
#include <sys/types.h>

void mysig_handler( int signum )
{
        printf("Received the signal: %d", signum );
}

int main( int argc, char *argv[] )
{

        pid_t chld;

        signal( SIGINT, mysig_handler );

        if( ( chld = fork() ) < 0 )
        {
                //error
                printf("Fork Error!\n");
        }
        else if( chld == 0 )
        {
                //child
                while(1)
                {
                }
        }
        else
        {
                //parent
                while(1)
                {
                }
        }
        return(0);
}
====================================================
my softwares are
gcc version egcs-2.91.66 19990314/Linux (egcs-1.1.2 release)
Kernel 2.2.14-12smp

Regards,
Vinay G.

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