On Aug 28, 10:42 pm, ole...@gmail.com (marcos rebelo) wrote:
> the idea is to process the STDOUT ad the STDERR.
>
> open don't do it
>
I was afraid you'd say that...
open3 is very liable to deadlock since you're trying to read from
both stderr and stdout. You'll very likely want to use IO::Select
to marshal when the read's occur and search for some sample
code.
>
> On Sun, Aug 29, 2010 at 6:08 AM, John W. Krahn <jwkr...@shaw.ca> wrote:
>
>
>
> > C.DeRykus wrote:
>
> >> Since you mention simplifying the code, do you actually
> >> need IPC::Open3 ? In your sample code, you're only
> >> reading process output.
>
> >> If you don't need IPC::Open3 complexity, you could just
> >> use magic open to read output :
>
> >> sub shell_run
> >> {
> >> print "YYYY";
> >> my $pid = open( my $fh, qq{ @_ | } ) or die "open: $!";
>
> > Probably better as:
>
> > my $pid = open my $fh, '-|', @_ or die "open: $!";
In general yes but here I don't think there's a benefit.
I believe perl will bypass the shell in both cases since
a list is passed. And, IIRC, perl launches a shell only
after parsing to see if it's absolutely required.
>
> > And you don't use $pid anywhere so why create it?
Agreed, I was trying to guage the OP's intention more
than cleaning up all the code.
>
> >> print for<$fh>;
>
> > Probably better as:
>
> > print while <$fh>;
Hm, I'd prefer 'while' as well but, though it may look odd, I
don't think there's been the penalty of 'for <$fh>' creating
and then iterating through a potentially large list for some
time.
>
> >> close $fh or die "close: ", $? || $!;
>
> > Probably better as:
>
> > close $fh or die $! ? "Error closing pipe: $!"
> > : "Exit status $? from $_[0]";
Definitely better. A child error might mask an
error for a full disk.
--
Charles DeRykus
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