IO::Select multiplexing

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

Hi, I'm trying to run the example in 'Network Programming with Perl' that does multiplex select. When I run the example code from the book (13.9, 13.10) I get the error: can't connect: Bad file descriptor

    The code fragment is:
# this is called to connect to remote host
sub connect {
  my $pack = shift;
  my ($host,$port) = @_;

  my $sock = IO::Socket::INET->new(Proto => 'tcp',
                                   Type  => SOCK_STREAM);
  return unless $sock;
  $sock->blocking(0);
  my $addr = sockaddr_in($port,inet_aton($host));
  my $result = $sock->connect($addr);
  return $sock if $result;  # return the socket if connected immediate
+ly
  return $sock if $! == EINPROGRESS;  # or if it's in progress
  return;                             # return undef on other errors
}
[download]

Any Ideas? NIge

Comment on IO::Select multiplexing Download Code

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Re: IO::Select multiplexing by Rudif (Hermit) on Jun 30, 2001 at 21:28 UTC
Did you type it in and perhaps mistyped something? For me, the example `web_fetch_p.pl + HTTPFetch.pm` worked straight out of the box - almost. I downloaded the example zip file from the book and unzipped it. Working on Win2k, I got this error on my first attempt to run it `"EINPROGRESS" is not exported by the Errno module at H:\devperl\socket +s\perl_networking\ch13\HTTPFetch.pm line 12` [download] I found a workaround `use POSIX qw(:errno_h); #use Errno 'EINPROGRESS';` [download] After this, I successfully retrieved a couple of perlmonks nodes: ours and yours Rudif Note: I also added the line to modify $localpath `$localpath .= "index.html" if $localpath =~ m!/$!; $localpath =~ s/[\?\=\&]/-/g; # Rudif` [download] so that the URL of a perlmonks node translates into a valid filename (HTTPFetch stores the retrieved URL content into a local file of similar name).	[reply] [d/l] [select]
Re: IO::Select multiplexing by jepri (Parson) on Jun 30, 2001 at 22:07 UTC
Naming your subroutines after perl builtins can cause a lot of trouble. How are you calling this routine? There's nothing in there that uses file descriptors, so what else is in your program. ____________________ Jeremy I didn't believe in evil until I dated it.	[reply]