PHP 7.0.6 Released

    ssh2_exec

    (PECL ssh2 >= 0.9.0)

    ssh2_exec — Execute a command on a remote server

    Description

    resource ssh2_exec ( resource $session , string $command [, string $pty [, array $env [, int $width = 80 [, int $height = 25 [, int $width_height_type = SSH2_TERM_UNIT_CHARS ]]]]] )

    Execute a command at the remote end and allocate a channel for it.

    Parameters

    session

    An SSH connection link identifier, obtained from a call to ssh2_connect().

    command

    pty

    env

    env may be passed as an associative array of name/value pairs to set in the target environment.

    width

    Width of the virtual terminal.

    height

    Height of the virtual terminal.

    width_height_type

    width_height_type should be one of SSH2_TERM_UNIT_CHARS or SSH2_TERM_UNIT_PIXELS.

    Return Values

    Returns a stream on success or FALSE on failure.

    Examples

    Example #1 Executing a command

    <?php
    $connection     = ssh2_connect('shell.example.com', 22);
    ssh2_auth_password($connection, 'username', 'password');

    $stream = ssh2_exec($connection, '/usr/local/bin/php -i');
    ?>

    See Also

    User Contributed Notes

    christopher dot millward at gmail dot com
    5 years ago
    There doesn't appear to be a way to get data from BOTH stderr and stdout streams simultaneously, or at least I've yet to find one.

    The following code *should* get the error message written to stderr, but if the call to stream_get_contents() for stdout is run first, the subsequent call for stderr won't return anything. 

    If the order of the statements is reversed, the call for stderr will return any errors and call for stdout will return nothing

    <?php
    // Run a command that will probably write to stderr (unless you have a folder named /hom)
    $stream = ssh2_exec($connection, "cd /hom");
    $errorStream = ssh2_fetch_stream($stream, SSH2_STREAM_STDERR);

    // Enable blocking for both streams
    stream_set_blocking($errorStream, true);
    stream_set_blocking($stream, true);

    // Whichever of the two below commands is listed first will receive its appropriate output.  The second command receives nothing
    echo "Output: " . stream_get_contents($stream);
    echo     "Error: " . stream_get_contents($errorStream);

    // Close the streams       
    fclose($errorStream);
    fclose($stream);

    ?>

    My initial suspicion is that either a) I've done something wrong  or b) the blocking nature of both streams means that by the time first stream has received data and returned, the buffer for the second stream has already emptied.

    I've done preliminary tests with blocking disabled, but haven't had any luck there either.
    lko at netuse dot de
    8 years ago
    if you are using exec function, and have problems with a output > 1000 lines
    you should use 

    <?php
                    stream_set_blocking    ($stream, true);
                    while(    $line = fgets($stream)) {
                                flush();
                            echo     $line."<br />";
                    }
    ?>

    except

    <?php
                    stream_set_blocking    ($stream, true);
                   echo     stream_get_contents($stream);
    ?>
    jaimie at seoegghead dot com
    7 years ago
    I believe most of the problem that people are having here is that there is a misconception about what blocking *really* means.

    Blocking means a read from the *stream* will wait until there is data.  Not necessarily all the data from the application -- but *some*.  So it won't help you at all if you're executing a command that doesn't write to stdout, or writes a whole lot of data.

    So there are 2 problems:

    1. If you need to know that a silent program is done via ssh2_exec, you'll need to signal it to yourself.  ssh2_exec will *not* block execution until the command is done executing.  And 2 consecutive ssh2_execs may execute asynchronously.  You could also log into a shell via ssh2_shell and parse up to the next prompt -- but that's overkill.  You can also do this by adding on some sort of sentinel at the end of your command, such as echo "@," and then block on reads until you see a "@."  Ensure "@" won't appear in the output, or escape the output via some encoding mechanism if you can't do that.

    2. If the program takes awhile, you have the same problem.  You need to read until you're done.  So you need a sentinel value like the above.

    3. Sleep() is just a bad idea here.  Commands rarely take the same amount of time to execute a command twice.  It may be OK if you're doing *one* thing and can just wait 5 seconds.  But that's not cool if it's something you're doing in a loop.

    Hope this helps!
    yairl at savion dot huji dot ac dot il
    10 years ago
    If you want to run many exec orders throught ssh2 in the same process using the same variable $stream for exemple and to read the output for each order, you must close the stream after each order else you will not be able to read the next order output.

    <?php
    $stream    =ssh2_exec($conn_id,"/usr/bin/ls .");
            stream_set_blocking( $stream, true );
            $cmd=fread($stream,4096);
    fclose($stream);

    if(    ereg("public_html",$cmd)){
    // ...........................................
    }

    $stream=ssh2_exec($conn_id,"/usr/bin/ls public_html");
            stream_set_blocking( $stream, true );
            $cmd=fread($stream,4096);
    fclose($stream);

    if(    ereg("images",$cmd)){
    // ..........................................
    }


    $stream=ssh2_exec($conn_id,"/usr/bin/ls public_html/images");
            stream_set_blocking( $stream, true );
            $cmd=fread($stream,4096);
    fclose($stream);

    if(    ereg("blabla",$cmd)){
    // ..........................................
    }
    ?>
    magicaltux at php dot net
    7 years ago
    The "pty" parameter is not documented.

    You should pass a pty emulation name ("vt102", "ansi", etc...) if you want to emulate a pty, or NULL if you don't.

    Passing false will convert false to a string, and will allocate a "" terminal.
    gakksimian at yahoo dot com
    10 years ago
    Executing remote Windows commands...
    After some hair pulling, I thought I'd suggest a couple things that might help others:

    1. Use 'ssh2_fetch_stream' to open a stderr stream according to the manual.
    2. Windows shell commands require 'cmd /C [command]' to execute.  (I had forgotten this)

    <?php
            // code fragment
            $stdout_stream = ssh2_exec($connection, 'cmd /C dir');
            $stderr_stream = ssh2_fetch_stream($stdout_stream, SSH2_STREAM_STDERR);
    ?>

    I didn't realize the need for the 'cmd /C' until I saw the stderr response 'dir: not found'.
    tabber dot watts at gmail dot com
    10 years ago
    This is the best way I found to automatically run multiple commands or commands that might take longer then expected.  NOTE: this assumes that no where in the output is there the text '[end]' otherwise the function will end prematurely.  Hope this helps people.

    <?php
    $ip     = 'ip_address';
    $user = 'username';
    $pass = 'password';

    $connection = ssh2_connect($ip);
    ssh2_auth_password($connection,$user,$pass);
    $shell = ssh2_shell($connection,"bash");

    //Trick is in the start and end echos which can be executed in both *nix and windows systems.
    //Do add 'cmd /C' to the start of $cmd if on a windows system.
    $cmd = "echo '[start]';your commands here;echo '[end]'";
    $output = user_exec($shell,$cmd);

    fclose($shell);

    function     user_exec($shell,$cmd) {
          fwrite($shell,$cmd . "\n");
          $output = "";
          $start = false;
          $start_time = time();
          $max_time = 2; //time in seconds
          while(((time()-$start_time) < $max_time)) {
            $line = fgets($shell);
        if(!    strstr($line,$cmd)) {
          if(    preg_match('/\[start\]/',$line)) {
                $start = true;
          }elseif(    preg_match('/\[end\]/',$line)) {
            return     $output;
          }elseif(    $start){
                $output[] = $line;
          }
        }
      }
    }

    ?>

    [EDIT BY danbrown AT php DOT net: Contains a bugfix supplied by (jschwepp AT gmail DOT com) on 17-FEB-2010 to fix a typo in a function name.]
    Betsy Gamrat
    9 years ago
    If the ssh2_exec takes awhile to run, and you need a handshake, you can use a file.  In this case, $flag names a handshake file that is written when the ssh script finishes.

    <?php
                    $stream     = ssh2_exec($connection, $command . " $public_key $private_key;");
                        $i=0;
                    while (!    file_exists ($flag) && ($i < MAX_TIME))
                    {
                                sleep(1);
                                $i++;
                    }
                        $ret_val=($stream!=FALSE);
    ?>

    This is an extract out of the bash script that is running.  Be sure to allow the webserver permission to read the file that the script writes.

    echo 0 > $OUTFILE
    chmod 666 $OUTFILE

    One other note:  you can put more than one command in by separating them with ';' (semicolons).
    mbs
    10 months ago
    <?php
    $connection     = ssh2_connect('shell.example.com', 22);
    ssh2_auth_password($connection, 'username', 'password');

    $stream = ssh2_exec($connection, '/usr/local/bin/php -i');
    ?>
    Betsy Gamrat
    9 years ago
    It is also good to use register_shutdown_function to shred the keys after this runs.
    Jon-Eirik Pettersen
    9 years ago
    The command  may not finish before the function return if the stream is not set to blocking mode. You may have to set the stream to blocking mode in order to get any output from the command.

    <?php
          // [Open connection]
      // ...

          $stream = ssh2_exec($connection, 'ps ax');
          stream_set_blocking($stream, true);
     
          // The command may not finish properly if the stream is not read to end
          $output = stream_get_contents($stream);
     
          // ...
      // [Close stream and connection]
    ?>
    Jim
    5 years ago
    It is important to note that this will not work ~all~ hosts that allow SFTP. We deny shell access, but allow SFTP using the sftp-internal subsystem.

    When attempting to use ssh2_exec() with this configuration, and stream_set_blocking set to true, the script will hang indefinitely. When stream_set_blocking is set to false, nothing will be returned.

    Even if you can SFTP files, be sure to check with your host to see if you have shell access.
    gwinans at gmail dot com
    6 years ago
    Oddly enough, I've noticed if I attempt to execute anything nothing happens. Now, I don't mean "No content is returned!".. I mean, "The command I told it to execute didn't execute!".

    Unless the following pattern is followed:

    <?php
    $stream     = ssh2_exec($connection, "touch ~/some_fake_file", 'xterm');
    stream_get_contents($stream);
    ?>

    Nowhere in the manual does it imply that stream_get_contents is required for the actual execution to take place, but in this case.. it seems that way. So, if you're having trouble getting commands to execute, try using stream_get_contents().
    noreply at voicemeup dot com
    3 years ago
    *** IMPORTANT ***
    If you are having issues getting STDERR on PHP 5.2.X, make sure to update to 5.2.17 and latest ssh2 extension from PECL.
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