PHP writing to a file from an output stream only writes the first few lines

Question

I am trying to write to a file (file.txt) from an output stream from a remote server. The output stream's content is generated from a bash/expect script on a remote server. I am not sure how fwrite() works, however, when I echo the fget() I can see the whole output from the script.

Does anyone know if fwrite() only writes the first few lines of the output stream? Or when does it stop writing? I have tried using a while loop to get it to continuously to write but I only see the first few lines in my file.txt while($line = fgets($stream_out)) {fwrite($fopenText, $line);} . However, when I echo the fget() I can see the whole output stream on the webpage I need the full output to be written to my file.txt, which is not doing.

How can I accomplish this?

$gwUser = 'user';
$gwPwd = 'pwd';
$pathToScript1 = '/home/user/up.sh';
$pathToScript2 = '/home/user/down.sh';

if ($connection = @ssh2_connect($gateway, 22)) {
    ssh2_auth_password($connection, $gwUser, $gwPwd);            
    if(isset($_POST['option']) && $_POST['option'] == 1) { 
        $stream = ssh2_exec($connection, $pathToScript1);
        stream_set_blocking($stream, true);
        $stream_out = ssh2_fetch_stream($stream, SSH2_STREAM_STDIO);
        $stream_err = ssh2_fetch_stream($stream, SSH2_STREAM_STDERR);

        $path = $_SERVER['DOCUMENT_ROOT'] . "/my/path/file.txt";
        touch($path);
        chmod($path, 0777);
        $fopenText = fopen($path, "w");
        while($line = fgets($stream_out)) {fwrite($fopenText, $line);} //this doesn't give me the full output stream
        echo '<pre>' . "------------------------\n" . '</pre>';
        while($line = fgets($stream_err)) {flush(); echo '<pre>' . $line . '</pre>';}
        fclose($stream);
        fclose($fopenText);
    }

    //I can get the the output stream this way, but this is not what i want.
    if(isset($_POST['option'])  && $_POST['option'] == 2) { 

        $stream = ssh2_exec($connection, "$pathToScript2");
        stream_set_blocking($stream, true);
        $stream_out = ssh2_fetch_stream($stream, SSH2_STREAM_STDIO);
        $stream_err = ssh2_fetch_stream($stream, SSH2_STREAM_STDERR);
        while($line = fgets($stream_out)) {flush(); echo '<pre>' . $line . '</pre>';}
        echo '<pre>' . "------------------------\n" . '</pre>';
        while($line = fgets($stream_err)) {flush(); echo '<pre>' . $line . '</pre>';}
        fclose($stream);                
    }
}

file.txt output:

[root@psat main]# cat file.txt
cd /home/user/
My current directory is:/home/user
./myExpectScript.sh

expected file.txt output (what i get back from $_POST['option'] == 2 echo):

cd /home/user/
My current directory is:/home/user/
./myExpectScript.sh
spawn /bin/bash
[user@gateway user]$ spawn /bin/bash
[user@gateway user]$ ./hexMsg -o 3 20000 0 0 0
??
[user@gateway user]$ /usr/local/bin/ssh " @ "
...
...
(omitted for simplicity)

Answer 1

It sounds like the SSH connection hasn't returned, so the fwrite() loop hasn't finished and the file isn't closed. As a result, some of the output may be buffered. Try flushing the buffer after each write:

    while($line = fgets($stream_out)) {
        fwrite($fopenText, $line);
        fflush($fopenText);
    }