OpenSSH server on Windows refusing to work without STDIN even in noninteractive mode

It the end, I've written this ssh wrapper to work around buggy windows OpenSSH servers which require STDIN even for noninteractive commands which do not use it:

#!/usr/bin/perl

use strict;
use warnings;
use Net::OpenSSH;

my $HOSTNAME = shift;
my $ssh = Net::OpenSSH->new($HOSTNAME);

my ($in_pipe, undef, undef, $pid) =
    $ssh->open_ex( { stdin_pipe => 1 }, @ARGV) or die "open_ex failed: " . $ssh->error;

waitpid($pid, 0);

It only uses hostname and command with arguments to run, no other parameters are allowed (I set them in ~/.ssh/config), so you run the script (for example) as myssh winserver whoami < /dev/null. It is just a wrapper around ssh client, which provides fake STDIN, and thus allows noninteractive ssh sessions to be run from cron(8) and atd(8)

Thanks Matija-Nalis for the question and solution. For other's gain, here's a crude python implementation.

ssh.py

import sys
import paramiko
client = paramiko.SSHClient()
client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
client.connect(sys.argv[2], username=sys.argv[1])
stdin, stdout, stderr = client.exec_command(sys.argv[3])
errlines = stderr.readlines()
outlines = stdout.readlines()
for l in outlines:
    print l.rstrip()
if len(errlines):
    print "WARNING: stderr generated:"
    for l in errlines:
        print l.rstrip()
exit(stdout.channel.recv_exit_status())

python ssh.py <user> <hostname> <command>

My use case was similar: Jenkins job failed to execute remote commands.

OpenSSH server on Windows refusing to work without STDIN even in noninteractive mode

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