Folks-

The following code seems to work between Sun_SSH_1.1.1 boxes. I don't know why it works, but it does. The secret ingredient was to add a system call that sent something to STDOUT before the system call (or exec) that does the ssh.

I'm guessing a bug in sshd on the target host. Any thoughts?

Thanks

-Craig 

use strict;
use warnings;

use IO::Select;

my $cmd = '"cat /etc/passwd"';

my $login = 'usr@host';
my $pkey = "$ENV{HOME}/.ssh/privateKey";

my @shell = ( '/usr/bin/ksh' => (
    -c => "$cmd",
));

my @sshcmd = ('/usr/bin/ssh' => (
    -t => (),
    -i => $pkey,
    -o => 'StrictHostKeyChecking no',
    $login,
    @shell,
));

if(my $child = open (IFILE, '-|')) {
    print STDERR "I'm the parent\n";
    print STDERR "Child pid=$child\n";
}else{
    select(STDIN); $|++;
    select(STDOUT); $|++;
    select(STDERR); $|++;
    print STDERR "I am the child\n";
    print "LINE 1...\n";
    print "LINE 2...\n";
    print "LINE 3...\n";
    print "LINE 4...\n";
    my $ret;
    $ret = system('echo hi');
    print STDERR "CHILD 1: ret=$ret\n";
    $ret = system(@sshcmd);
    print STDERR "CHILD 2: ret=$ret\n";
    print "LINE 5...\n";
    print "LINE 6...\n";
    print "LINE 7...\n";
    print "LINE 8...\n";
}

my $select = IO::Select->new();
$select->add(\*IFILE);

my @ready;
while ( @ready = $select->can_read(5) ) {
    foreach my $fh (@ready) {
        my $line = <$fh>;
print STDERR "line=$line";
        if(eof($fh)) {
            $select->remove($fh);
            close($fh) || warn "Close problem on fh: $fh";
        }
    }
}

close(IFILE);

[download]

In reply to Solution: Don't know why it works... by cmv
in thread IO::Select & ssh problem by cmv

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