Hi Monks,

the following code runs really strange and I don't know why. 
use strict;
use warnings;
use IPC::Open3;
&run;

sub run {
    while ( 1 ) {
        eval { &_run };
        print $@ if $@;
        sleep 10;
    }
}

sub _run {
    my ($wtr, $rdr, $err);
    my (@output, $pid);

    eval {
        $pid = IPC::Open3::open3($wtr, $rdr, $err, 'blubb');

        while (my $line = <$rdr>) {
            chomp($line);
            push @output, "out: $line";
        }

        close($wtr) if $wtr;
        close($rdr) if $rdr;
        close($err) if $err;
        waitpid $pid, 0;
    };

    print "$_\n" for @output;
}

[download]
If the function _run is call in a eval block then it produces every 10
seconds a new process. If it runs without eval, then it runs correctly.
I tried the same with IPC::Cmd, but there exists the same problem. 
use strict;
use warnings;
use IPC::Cmd;
&run;

sub run {
    while ( 1 ) {
        eval { &_run_cmd };
        print $@ if $@;
        sleep 10;
    }
}

sub _run_cmd {
    my( $success, $error_code, $full_buf, $stdout_buf, $stderr_buf ) =
            IPC::Cmd::run( command => 'blubb', verbose => 0 );
    print $success, "\n";
}

[download]
Why does eval makes it so strange?

Thank you for helping.

In reply to Problems with IPC::Open3 by Anonymous Monk

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