The new method for Net::SFTP::Foreign accepts a transport option that lets you control how the SSH transport is constructed.

Unfortunately it is not so simple as linking ssh stderr stream back to Perl through a pipe as it would block the child if you don't read from it at the right times, and that means going into the select loop at the core of Net::SFTP::Foreign.

But there is a simple work around, just send ssh stderr to a file and read it afterwards: 

use Net::SFTP::Foreign;
use File::Temp;

my $hostname = 'localhost';

my $ssherr = File::Temp->new or die "File::Temp->new failed";

open my $stderr_save, '>&STDERR' or die "unable to dup STDERR";
open STDERR, '>&'.fileno($ssherr);

my $sftp = Net::SFTP::Foreign->new($hostname, more => ['-v']);

# the child ssh process has already been created with the redirected S
+TDERR
# so we can reset it on the parent:
open STDERR, '>&'.fileno($stderr_save);

if ($sftp->error) {
  print "sftp error: ".$sftp->error."\n";
  seek($ssherr, 0, 0);
  while (<$ssherr>) {
    print "captured stderr: $_";
  }
}

close $ssherr;

[download]

In reply to Re^2: Net::SFTP::Foreign Connection STDERR by salva
in thread Net::SFTP::Foreign Connection STDERR by allyc

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.