fork in perl 5.8.3 on windows

[Josh Denny]

I am trying to write a simple file transfer server in perl that will
reside of both windows and linux platforms. Basically, it accepts a
connection, forks a process, and then should close the child. on
windows, it dies after "accumulati ng" 64 children opened - however,
they should all (or most) have exited by that time. Any idea how to
get my children to exit and free up space for more connections?

Thanks - Josh

here's the relevant part of my code:


sub reaper { #to eliminate dead child processess
$waitpid=wait;
$SIG{CHLD}=\&re aper;
}
$SIG{CHLD}=\&re aper;

main();

sub main {
my $contentlength;

print "Loading data transfer server on port
$datatransfer_p ort...\n\n";
socket_listen (\*SERVER, $datatransfer_p ort);
while (accept ($client, SERVER)) {
my ($c_port, $c_iaddr) = sockaddr_in(get peername($clien t));
my(@inetaddr) = unpack('C4', $c_iaddr);
my $from = join('.', @inetaddr);

if (my $pid = fork) { #if it is the server, then next
close $client or die "Client socket close failed: $!";
} elsif (defined $pid) { #a child
client_connect( $client, $from); #processes the clients connection
exit(0);
} else {
die "fork error: $!"; #program dies here after 64
client_connect' s
}
}
}

[Will Stranathan]

Re: fork in perl 5.8.3 on windows

josh.denny@vand erbilt.edu (Josh Denny) wrote in message news:<a3123321. 0403011830.2f82 de6d@posting.go ogle.com>...[color=blue]
> windows, it dies after "accumulati ng" 64 children opened - however,
> they should all (or most) have exited by that time. Any idea how to
> get my children to exit and free up space for more connections?
>[/color]

This is probably not necessary - if the parent doesn't CARE when the
child dies, you ought to just be able to say:
$SIG{CHLD} = 'IGNORE';
[color=blue]
> sub reaper { #to eliminate dead child processess
> $waitpid=wait;
> $SIG{CHLD}=\&re aper;
> }
> $SIG{CHLD}=\&re aper;[/color]

Take a look at client_connect and see why client_connect is hanging.[color=blue]
> while (accept ($client, SERVER)) {
> my ($c_port, $c_iaddr) = sockaddr_in(get peername($clien t));
> my(@inetaddr) = unpack('C4', $c_iaddr);
> my $from = join('.', @inetaddr);
>
> if (my $pid = fork) { #if it is the server, then next
> close $client or die "Client socket close failed: $!";
> } elsif (defined $pid) { #a child
> client_connect( $client, $from); #processes the clients connection
> exit(0);
> } else {
> die "fork error: $!"; #program dies here after 64
> client_connect' s
> }
> }
> }[/color]

[Jim Gibson]

Re: fork in perl 5.8.3 on windows

In article <a3123321.04030 11830.2f82de6d@ posting.google. com>, Josh
Denny <josh.denny@van derbilt.edu> wrote:
[color=blue]
> I am trying to write a simple file transfer server in perl that will
> reside of both windows and linux platforms. Basically, it accepts a
> connection, forks a process, and then should close the child. on
> windows, it dies after "accumulati ng" 64 children opened - however,
> they should all (or most) have exited by that time. Any idea how to
> get my children to exit and free up space for more connections?
>
> Thanks - Josh
>
> here's the relevant part of my code:
>
>
> sub reaper { #to eliminate dead child processess
> $waitpid=wait;
> $SIG{CHLD}=\&re aper;
> }
> $SIG{CHLD}=\&re aper;
>
> main();
>
> sub main {
> my $contentlength;
>
> print "Loading data transfer server on port
> $datatransfer_p ort...\n\n";
> socket_listen (\*SERVER, $datatransfer_p ort);
> while (accept ($client, SERVER)) {
> my ($c_port, $c_iaddr) = sockaddr_in(get peername($clien t));
> my(@inetaddr) = unpack('C4', $c_iaddr);
> my $from = join('.', @inetaddr);
>
> if (my $pid = fork) { #if it is the server, then next
> close $client or die "Client socket close failed: $!";
> } elsif (defined $pid) { #a child
> client_connect( $client, $from); #processes the clients connection
> exit(0);
> } else {
> die "fork error: $!"; #program dies here after 64
> client_connect' s
> }
> }
> }[/color]

My guess is that the client_connect routine is hanging up and not
returning, but without seeing the code it is really hard to tell. Print
out the PIDs in the parent and print the PID ($$) from the child just
before the exit(0) statement to tell for sure.

You might want to check out socket modules: Socket or IO::Socket.