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Reference Variables To A Child Process Created With Fork

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# 1  
Old 10-07-2001
Question Reference Variables To A Child Process Created With Fork
Hi!

IN THE FOLLOWING PROGRAM THE VALUE OF j REMAINS UNCHANGED . WHY ? IF I WANT A VARIABLE VALUE TO CHANGE LIKE THIS , IS THERE ANY WAY TO DO IT ?

Or do we have to use shared memory variables?

main()
{
int return_pid, i, total;
int j=1;
total = TOTALRECS+1;

for (i=0; i<NUMPROCESSES; i++)
if (fork() == 0)
child_code (i,total,&j);

for (i=0; i<NUMPROCESSES; i++)
return_pid = wait(0);

printf ("value of J <%d>\n", j);
}
# 2  
Old 10-07-2001
The short answer... yes, you should probably
use shared memory. Once you fork(),
you get a new process with it's own stack and
heap space (among other things).

BTW, I hope your code doesn't really look
like that Smilie
# 3  
Old 10-07-2001
Sounds like a homework problem to me...... Let's not answer homework problems, if we can avoid it. Thanks.
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