Perl 5.8从SSH命令获取标准输出

Question

I need to create a script that will work on CentOS 5.x and CentOS 6.x boxes. CentOS 5.x uses Perl 5.8 and CentOS 6.x uses Perl 5.10 . The goal is to be able to ssh into a box, that has a key exchange in place, then run python -V , to determine if the default version is python 2.6 .

I'm guessing if I get a script that works with Perl 5.8, that it'll work for 5.10 as well. I made some progress with Net::SSH:Any to have to throw it away, as it looks like it works with Perl 5.12 and newer.

I've tried IPC::System::Simple and qx as well, but haven't had luck capturing the output.

Some of my failed attempts:

Fail 1:

use IPC::System::Simple qw(system systemx capture capturex);
my $output = capture("/usr/bin/ssh root\@10.100.10.56 python -V");
print "out: " . $output . "\n";

Fail 2:

my $output = qx(ssh root\@10.100.10.56 python -V);
print "out: " . $output . "\n";

Fail 3:

my @output = qx(ssh root\@10.100.10.56 python -V);
print "@output\n";

I'm not sure if the call of ssh is playing with anything and am in desperate need of a sanity check. When the command is run, the output is shown on the screen, but not stored in the variable, which I can do substring checks against. The $output variable is left blank. If I'm missing something, please let me know. Thanks :)

Answer 1

Figured it out from ThisSuitIsBlackNot's advice. I found Getting STDOUT, STDERR, and response code from external *nix command in perl which showed me how to update my code to get stderr too, which is as follows:

my $output = qx(ssh root\@10.100.10.56 python -V 2>&1);
print "out: " . $output . "\n";

This gave me what I needed. Thx!