PHP期望：如何复制流的内容

Question

In this example: http://php.net/manual/en/expect.examples-usage.php, i.e.

<?php
ini_set("expect.timeout", -1);
ini_set("expect.loguser", "Off");

$stream = expect_popen("ssh root@remotehost");

while (true) {
    switch (expect_expectl ($stream, array (
            array ("password:", PASSWORD), // SSH is asking for password
            array ("yes/no)?", YESNO), // SSH is asking whether to store the host entry
            array ("~$ ", SHELL, EXP_EXACT), // We've got the shell!
    ))) {
        case PASSWORD:
            fwrite ($stream, "secret
");
            break;
....

How would I output the part of $stream that expect_expectl is currently working on?

Probably I haven't completely grasped the concepts and tools to work with streams.

I want to see each line of the stream regardless if it matches or not even if that's only for debugging purposes of my script.

Answer 1

If you look at the official documentation for expect_expectl(), you'll see that it takes a third argument which is populated with the current match. The entire line would be in $match[0] and matched segments in the following elements (much like preg_match()).

while (true) {
    switch (expect_expectl ($stream, array (
            array ("password:", PASSWORD), // SSH is asking for password
            array ("yes/no)?", YESNO), // SSH is asking whether to store the host entry
            array ("~$ ", SHELL, EXP_EXACT), // We've got the shell!
            array (".*", 'ALL', EXP_REGEXP), // Unmatched lines
    ), $match)) {
        case PASSWORD:
            echo $match[0];
            fwrite ($stream, "secret
");
            break;
        /* other cases */
        case 'ALL':
            echo $match[0];