Expect Functions

Introduktion

This extension allows to interact with processes through PTY. You may consider using the expect:// wrapper with the filesystem functions which provide a simpler and more intuitive interface.

Systemkrav

This module uses the functions of the » expect library. You need libexpect version >= 5.43.0.

Installation

Denne » PECL udvidelse medfølger ikke i PHP. Uddybende information så som nye udgivelser, downloads, kildekoder, vedligeholder information samt en CHANGELOG, kan findes her: » https://pecl.php.net/package/expect.

I PHP 4 er denne PECL udvidelses kildekode kan blive fundet i ext/ biblioteket inde i PHP kildekoden eller ved PECL linket ovenover. In order to use these functions you must compile PHP with expect support by using the --with-expect[=DIR] configure option.

Windows users will enable php_expect.dll inside of php.ini in order to use these functions. I PHP 4 befinder denne DLL sig i extensions/ biblioteket inde i PHP Windows binær download. Du kan hente denne PECL udvidelse DLL fra » PHP Downloads siden eller på » https://snaps.php.net/.

Runtime Konfiguration

Virkemåden af disse funktioner er berørt af indstillinger i php.ini.

In order to configure expect extension, there are configuration options in the configuration file php.ini.

**Expect Configure parametre**
Navn	Standard	Foranderlig
expect.timeout	"10"	PHP_INI_ALL
expect.loguser	"1"	PHP_INI_ALL
expect.logfile	""	PHP_INI_ALL

For flere detaljer og definationer af PHP_INI_* constanterne, se ini_set() dokumentation.

Her er en kort forklaring på konfigurations-direktiverne.

expect.timeout integer

The timeout period for waiting for the data, when using the expect_expectl() function.

A value of "-1" disables a timeout from occurring.

Note: A value of "0" causes the expect_expectl() function to return immediately.

expect.loguser boolean

Whether expect should send any output from the spawned process to stdout. Since interactive programs typically echo their input, this usually suffices to show both sides of the conversation.

expect.logfile string

Name of the file, where the output from the spawned process will be written. If this file doesn't exist, it will be created.

Note: If this configuration is not empty, the output is written regardless of the value of expect.loguser.

Ressourcetyper

expect_popen() returns an open PTY stream used by expect_expectl().

Foruddefinerede Konstanter

Konstanterne nedenunder er defineret af denne udvidelse, og vil kun være tilgængelige når denne udvidelse enten er blevet kompileret ind i PHP eller dynamisk indsat under runtime.

EXP_GLOB (integer): Indicates that the pattern is a glob-style string pattern.
EXP_EXACT (integer): Indicates that the pattern is an exact string.
EXP_REGEXP (integer): Indicates that the pattern is a regexp-style string pattern.
EXP_EOF (integer): Value, returned by expect_expectl(), when EOF is reached.
EXP_TIMEOUT (integer): Value, returned by expect_expectl() upon timeout of seconds, specified in value of expect.timeout
EXP_FULLBUFFER (integer): Value, returned by expect_expectl() if no pattern have been matched.

Eksempler

This example connects to the remote host via SSH, and prints the remote uptime.

Example#1 Expect Usage Example


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

$stream = fopen ("expect://ssh root@remotehost uptime", "r");

$cases = array (
  array (0 => "password:", 1 => PASSWORD)
);

switch (expect_expectl ($stream, $cases)) {
 case PASSWORD:
  fwrite ($stream, "password\n");
  break;
 
 default:
  die ("Error was occurred while connecting to the remote host!\n");
}

while ($line = fgets ($stream)) {
  print $line;
}
fclose ($stream);
?>

The following example connects to the remote host, determines whether installed OS is for 32 or 64 bit, then runs update for specific package.

Example#2 Another Expect Usage Example


<?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\n");
            break;

        case YESNO:
            fwrite ($stream, "yes\n");
            break;

        case SHELL:
            fwrite ($stream, "uname -a\n");
            while (true) {
                    switch (expect_expectl ($stream, array (
                            array ("~$ ", SHELL, EXP_EXACT), // We've got the shell!
                            array ("^Linux.*$", UNAME, EXP_REGEXP), // uname -a output
                    ), $match)) {
                        case UNAME:
                            $uname .= $match[0];
                            break;
                        
                        case SHELL:
                            // Run update:
                            if (strstr ($uname, "x86_64")) {
                                    fwrite ($stream, "rpm -Uhv https://mirrorsite/somepath/some_64bit.rpm\n");
                            } else {
                                    fwrite ($stream, "rpm -Uhv https://mirrorsite/somepath/some_32bit.rpm\n");
                            }
                            fwrite ($stream, "exit\n");
                            break 2;
                    
                        case EXP_TIMEOUT:
                        case EXP_EOF:
                            break 2;

                        default:
                            die ("Error has occurred!\n");
                    }
            }
            break 2;

        case EXP_TIMEOUT:
        case EXP_EOF:
            break 2;

        default:
            die ("Error has occurred!\n");
    }
}

fclose ($stream);
?>

expect_expectl — Waits until the output from a process matches one of the patterns, a specified time period has passed, or an EOF is seen
expect_popen — Execute command via Bourne shell, and open the PTY stream to the process