in reply to Re^2: Handling STDERR when using Net::OpenSSH
in thread Handling STDERR when using Net::OpenSSH

Can you please describe (or show relevant code) of your setup in a bit more detail just so we can understand your situation better?

I think your setup is something like the following:

local machine                remote machine
script         Net::OpenSSH  fastCGI script

[download]

... and you want to run the fastCGI script and get its output?

Maybe you can also show us how you're starting the fastCGI script exactly. Maybe FastCGI is happier with having actual filehandles (with inodes), or it wants a /dev/tty or a domain socket to interact with, instead what Net::OpenSSH provides directly.

A nasty alternative could be to set up just enough of Apache (or another FastCGI environment using Net::FastCGI or whatever), and then access the script via http...

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Re^4: Handling STDERR when using Net::OpenSSH
by Anonymous Monk on May 15, 2018 at 07:59 UTC

    I mean I have an apache application, using CGI::Fast (which uses FCGI). This application is working happily.

    Now I'm trying to add a request handler that upon receiving a request via apache, it will attempt to use Net::OpenSSH to connect to a remote host

    The issue is FCGI / CGI::Fast have captured and redirected the STDIN/STDOUT/STDERR filehandles and Net::OpenSSH dies when I try to create a new Net::OpenSSH object

    Abbreviated code below

    use CGI::Fast;
while (my $r = CGI::Fast->new) {
        open my $stderr_fh, '>', 'some_file';
        open my $stdin_fh, '<', '/dev/null';
        open my $stdout_fh, '>', 'some_other_file';

        my %options = (
                batch_mode => 1,
                timeout => 10,
                kill_ssh_on_timeout => 1,
                default_stdout_discard => 1,
                default_stderr_discard => 1,
                master_stderr_fh => $stderr_fh,
                master_stdout_fh => $stdout_fh,
        );

        my $ssh = Net::OpenSSH->new('test@192.168.0.123', %options);
}

    [download]

    The errors invariably occur inside the Net::OpenSSH->new() call

[reply]
[d/l]
      Try with default_stdin_fh => $stdin_fh.

      Also, enable debugging in order to see what is happening: $Net::OpenSSH::debug=127;.

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[select]

        Even with default_stdin_fh set, I still get the error Operation 'OPEN' not supported on FCGI::Stream handle at \/usr\/share\/perl5\/Net\/OpenSSH.pm line 761.

        STDERR output from debug doesn't show anything obviously informative to me?

         open_ex: ['ssh','-V'], referer: http://127.0.0.1/test_ssh.pl
 io3 mloop, cin: 0, cout: 1, cerr: 0, referer: http://127.0.0.1/test_s
+sh.pl
 io3 fast, cin: 0, cout: 1, cerr: 0, referer: http://127.0.0.1/test_ss
+h.pl
 stdout, bytes read: 60 at offset 0, referer: http://127.0.0.1/test_ss
+h.pl
 io3 fast, cin: 0, cout: 1, cerr: 0, referer: http://127.0.0.1/test_ss
+h.pl
 stdout, bytes read: 0 at offset 60, referer: http://127.0.0.1/test_ss
+h.pl
 leaving _io3(), referer: http://127.0.0.1/test_ssh.pl
 waiting for slave, timeout: 10, remaining: 10, sleep: 1, referer: htt
+p://127.0.0.1/test_ssh.pl
 _waitpid(27399) => pid: 27399, rc: 0, err: Interrupted system call, r
+eferer: http://127.0.0.1/test_ssh.pl
 OpenSSH version is 7.2p2, referer: http://127.0.0.1/test_ssh.pl
 ctl_path: /tmp/.net_ssh/monitor-192.168.0.12-27394-236253, ctl_dir: /
+tmp/.net_ssh/, referer: http://127.0.0.1/test_ssh.pl
 set_error(0 - 0), referer: http://127.0.0.1/test_ssh.pl
 call args: ['ssh','-o','ConnectTimeout=10','-o','ServerAliveInterval=
+10','-o','ServerAliveInterval=30','-o','ControlPersist=no','-2MNx','-
+o','BatchMode=yes','-i','/tmp/.5SFO0niU.27394.key','-o','PreferredAut
+hentications=publickey','-S','/tmp/.net_ssh/monitor-192.168.0.12-2739
+4-236253','-l','monitor','192.168.0.123','--'], referer: http://127.0
+.0.1/test_ssh.pl
 master state jumping from _STATE_START to _STATE_AWAITING_MUX, refere
+r: http://127.0.0.1/test_ssh.pl
 file object not yet found at /tmp/.net_ssh/monitor-192.168.0.12-27394
+-236253, state:_STATE_AWAITING_MUX, referer: http://127.0.0.1/test_ss
+h.pl
 DESTROY(Net::OpenSSH=HASH(0x5db2ac0), pid: <undef>), referer: http://
+127.0.0.1/test_ssh.pl
 set_error(1 - aborted), referer: http://127.0.0.1/test_ssh.pl
 master state jumping from _STATE_START to _STATE_GONE, referer: http:
+//127.0.0.1/test_ssh.pl

        [download]
[reply]
[d/l]

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