ssh-sftp-perl-users

[Ssh-sftp-perl-users] Net::SSH2 don't see the result of commands

[Serge L. <ser...@gm...>]

HI,

I'm trying to see the result of executing "uname -a" on my host.
Unfortunately, there is no  output from the script.
Could you please point me what I do wrong?

I tried to do it with opensuse 10.2 and  FC 5, perl v5.8.8,
*libssh2-0.14 , Net-SSH2-0.09
*
Note:  Everything is ok If I do the following

$chan->exec('uname -a > /tmp/my');
my $sftp = $ssh2->sftp() or die $!;
my $fh = $sftp->open('/tmp/my') or die $!;
print $_ while <$fh>;

so the lib and module are working, but I guess it's a bad way.


Script:
--------------------------------------8<-----------------------------------------
#!/usr/bin/perl -w
use strict;
use Net::SSH2;

my $ssh2 = Net::SSH2->new();

print "connect fail\n" unless ($ssh2->connect('127.0.0.1'));
print "password fail\n" unless ($ssh2->auth_password('root', 'xxx'));

# test1
my $chan=$ssh2->channel();
$chan->shell();
print $chan "uname -a\n";
print "LINE : $_" while <$chan>;
$chan->close;

# test2
 $chan=$ssh2->channel();
$chan->exec('uname -a');
while (<$chan>){ print $_ } ;
$chan->close;

exit 0
--------------------------------------8<-----------------------------------------

-- 
  Sincerely
     Serge Leschinsky 

Re: [Ssh-sftp-perl-users] Net::SSH2 don't see the result of commands

[David R. <dbr...@cp...>]

On Saturday February 10, 2007 09:30, Serge Leschinsky wrote:
> I'm trying to see the result of executing "uname -a" on my host.
> Unfortunately, there is no  output from the script.
> Could you please point me what I do wrong?

Both your test1 and test2 scripts below works fine for me (using Gentoo Linux, 
perl 5.8.8, Net::SSH2 0.09).  Try adding a sleep(5) before you start reading 
the output, to see if it's just an output delay.

-- 
Dave
Isa. 40:31

Re: [Ssh-sftp-perl-users] Net::SSH2 don't see the result of commands

[Serge L. <ser...@gm...>]

David Robins wrote:
> On Saturday February 10, 2007 09:30, Serge Leschinsky wrote:
>> I'm trying to see the result of executing "uname -a" on my host. 
>> Unfortunately, there is no  output from the script. Could you please point
>> me what I do wrong?
> 
> Both your test1 and test2 scripts below works fine for me (using Gentoo
> Linux, perl 5.8.8, Net::SSH2 0.09).  Try adding a sleep(5) before you start
> reading the output, to see if it's just an output delay.
> 
Thank you for the replay. I've tried, but got the same result...
But I did another test and, really, it can be clue.

What I do:
1. execute script with _long_ command
2. measure time of executing for script - really the time depends on 		sleep(5);
3. check if the process exists.

It looks like the $chan->exec() detach control terminal. It's very useful
behavior but how can I manage it (I mean how to define detach or keep stdin,
stdout etc)?

May I ask you to help me in this? Probably I just missed something important in
the manual for Net::SSH2.


[root@lx-sles ~]# cat 123
#!/usr/bin/perl -w
use strict;
use Net::SSH2;

my $ssh2 = Net::SSH2->new();
print "connect fail\n" unless ($ssh2->connect('127.0.0.1'));
print "password fail\n" unless ($ssh2->auth_password('root', 'xxxx'));
# test2

my $chan=$ssh2->channel();
$chan->exec('LIMIT=10 ; for ((a=1; a <= LIMIT ; a++)) ; do expr 2 \* $a ; sleep
10;  done') or warn $!;
sleep(5);
while (<$chan>){ print $_ } ;
$chan->close;

exit 0

[root@lx-sles ~]# time ./123

real    0m5.245s
user    0m0.104s
sys     0m0.008s

[root@lx-sles ~]# ps axf
.......
12273 ? Ss 0:00 bash -c LIMIT=10 ; for ((a=1; a <= LIMIT ; a++)) ; do expr 2 \*
12293 ? S  0:00  \_ sleep 10


-- 
  Sincerely
     Serge Leschinsky