Posted by Shawn McKnight on 05/16/05 05:14

I ran in to many ssh2 stream problems as well.

Problem 1.
One problem I think related to the openssl version I was using.
I was using the standard version with Fedora Core 3. ssh connected actions
sometimes worked and sometimes did not work.

I recompiled the ssh2.so with the following versions.

libssh2-0.8
openssl-0.9.7g
ssh2-0.7

Problem 2.
At this point file transfers worked great. However, running commands and
reading the stream was having problems.

Using the classic

<?
| while (!feof($ssh_stream)) {
$contents .= fread($||ssh_stream||, 5120);
}
?>

I found that I never got any responses.
After testing I found that my $||ssh_stream always had a true response
to feof($||ssh_stream||)|;
And that fread($ssh_stream,5120) did not always bring back data.

While the following is not a Correction to the problem, it does allow
you to read the incoming stream
and know when it is done computing. This is the function I use which is
in side a remoteConnection
class I have wrapping the different ssh2 functions. If somebody comes up
with a "CORRECTIOIN" to
the problem rather than a work around, I would surely appreciate it.

Here is my work around with comments. Hope it helps.

<?

function command ($command) {
// attach "echo '__end_cmd_response__';" to the end of any
command run.
// this will be the last thing in the streams output so I
can identify when my command
// has finished.
$stream = ssh2_exec($this->conn, $command ."\necho
'__end_cmd_response__';" );
if ($stream) {
// not fully sure why I do this. but it does not seem to
hurt. The stream has no data
// right away.
sleep(5);
// turning blocking off allows stream to keep moving
eventhough no data is coming
// through it. Required to make the time out work correctly.
socket_set_blocking($stream,false);
// the time out is set less than the php time out.
Otherwise you run the risk of the
// php timing out if the stream hangs.
stream_set_timeout($stream,25);
$start = mktime();
// manual indicator to exit the while
$exit = false;
while ($exit == false) {
$read .= fread($stream,5120);
// this pulls meta data from the stram so we can
test for the time out.
$info = stream_get_meta_data($stream);
// test for the echo'ed __end_cmd_response__
if (ereg("__end_cmd_response__",$read)) {
$exit = true;
break;
// check to see if the stream has timed out.
} elseif ($info["timed_out"]) {
// i just add this to tell the user that the
stream timed out.
$read .= "<i>Exited stream reading (25 seconds).
Check changes online.</i>\n";
$exit = true;
break;
}
}
fclose($stream);
return $read;
}

?>

Oscar Gosdinski wrote:

>Hello everybody:
>
>I need my PHP application connects through SSH to other server for
>getting some info to display and i tried the following code to test
>lib ssh2:
>
>$server = ...;
>$user = ...;
>$passwd = ...;
>
>$con = ssh2_connect($server, 22);
>if (ssh2_auth_password($con, $user, $passwd)) {
> $s = ssh2_exec($con, 'ls -l');
> $file = fopen("/tmp/test", "w");
> while ($line = stream_get_line($s, 1024)) {
> fwrite($file, $line);
> fflush($file);
> }
> fclose($file);
>} else {
> echo "Authentication Error";
>}
>
>The file /tmp/test was created but it does not have any data. I can
>connect to the server using a normal ssh session in my laptop and the
>'ls -l' command returns me information.
>I think that i installed correctly the ssh2 functions because if a put
>an incorrect password i get the "Authentication Error" message.
>
>I searched the web for info about similar problems and no results.
>Please, anyone can help me with this problem because i have been
>spending three days with this.
>
>Thanks in advance for your answers.
>
>
>

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