Re^2: Weirdness with IO::Select and IPC::Open3

Hi ikegami, thanks for all the great responses. It's going to take me a while to study it all, but I was wondering--how would you do it without IO::Select? You seem to be suggesting it is less than ideal for the purpose, but all I know is when I google the errors I get when I don't use it, everyone says to use it :-).

Color me confused.

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Re^3: Weirdness with IO::Select and IPC::Open3 by ikegami (Patriarch) on Mar 21, 2011 at 04:40 UTC
If you don't care about the child's STDERR, you can send it to the parent's STDERR (using `'>STDERR'` for `open3`'s third arg). Then, all you need is `... while (<$stdout_fh>) { chomp; if (/Have a nice day!\z/) { print("$query\n"); } elsif ($answers{$query}) { print($stdin_fh "$answers{$query}\n"); } else { # ...[ Do something with unrecognised output from STDIN. ]... } }` [download] You can do this because you have a strict request-response protocol. If you had a more asynchronous protocol, you still have lots of simpler options than `select`. These include IPC::Run, Expect and threads. when I google the errors I get when I don't use it, everyone says to use it :-). What errors would that be?	[reply] [d/l] [select]

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Re^3: Weirdness with IO::Select and IPC::Open3
by ikegami (Patriarch) on Mar 21, 2011 at 04:40 UTC

If you don't care about the child's STDERR, you can send it to the parent's STDERR (using '>STDERR' for open3's third arg). Then, all you need is

...

while (<$stdout_fh>) {
   chomp;
   if (/Have a nice day!\z/) {
      print("$query\n");
   } elsif ($answers{$query}) {
      print($stdin_fh "$answers{$query}\n");
   } else {
       # ...[ Do something with unrecognised output from STDIN. ]...
   }
}
[download]

You can do this because you have a strict request-response protocol.

If you had a more asynchronous protocol, you still have lots of simpler options than select. These include IPC::Run, Expect and threads.

when I google the errors I get when I don't use it, everyone says to use it :-).

What errors would that be?

[reply]
[d/l]
[select]