streamWrapper::dir_readdir

(PHP 4 >= 4.3.2, PHP 5, PHP 7, PHP 8)

streamWrapper::dir_readdirRead entry from directory handle

Beschreibung

public function streamWrapper::dir_readdir(): string|bool

This method is called in response to readdir().

Parameter-Liste

Diese Funktion besitzt keine Parameter.

Rückgabewerte

Should return string representing the next filename, or false if there is no next file.

Warnung

Returning true or false will have the same effect of signaling there is no next file. However, returning true is discouraged and false should be used to signal this condition instead.

Hinweis:

A non-boolean return value will be casted to string.

Fehler/Exceptions

Wirft E_WARNING, wenn der Aufruf dieser Methode fehlschlug (z. B. weil sie nicht implementiert ist).

Beispiele

Beispiel #1 Listing files from tar archives

<?php
class streamWrapper {
    protected $fp;

    public function dir_opendir($path, $options) {
        $url = parse_url($path);

        $path = $url["host"] . $url["path"];

        if (!is_readable($path)) {
            trigger_error("$path isn't readable for me", E_USER_NOTICE);
            return false;
        }
        if (!is_file($path)) {
            trigger_error("$path isn't a file", E_USER_NOTICE);
            return false;
        }

        $this->fp = fopen($path, "rb");
        return true;
    }

    public function dir_readdir() {
        // Extract the header for this entry
        $header      = fread($this->fp, 512);
        $data = unpack("a100filename/a8mode/a8uid/a8gid/a12size/a12mtime/a8checksum/a1filetype/a100link/a100linkedfile", $header);

        // Trim the filename and filesize
        $filename    = trim($data["filename"]);

        // No filename? We are the end of the archive
        if (!$filename) {
            return false;
        }

        $octal_bytes = trim($data["size"]);
        // Filesize is defined in octets
        $bytes       = octdec($octal_bytes);

        // tar rounds up filesizes up to multiple of 512 bytes (zero filled)
        $rest        = $bytes % 512;
        if ($rest > 0) {
            $bytes      += 512 - $rest;
        }

        // Seek over the file
        fseek($this->fp, $bytes, SEEK_CUR);

        return $filename;
    }

    public function dir_closedir() {
        return fclose($this->fp);
    }

    public function dir_rewinddir() {
        return fseek($this->fp, 0, SEEK_SET);
    }
}

stream_wrapper_register("tar", "streamWrapper");
$handle = opendir("tar://example.tar");
while (false !== ($file = readdir($handle))) {
    var_dump($file);
}

echo "Rewinding..\n";
rewind($handle);
var_dump(readdir($handle));

closedir($handle);
?>

Das oben gezeigte Beispiel erzeugt eine ähnliche Ausgabe wie:

string(13) "construct.xml"
string(16) "dir-closedir.xml"
string(15) "dir-opendir.xml"
string(15) "dir-readdir.xml"
string(17) "dir-rewinddir.xml"
string(9) "mkdir.xml"
string(10) "rename.xml"
string(9) "rmdir.xml"
string(15) "stream-cast.xml"
string(16) "stream-close.xml"
string(14) "stream-eof.xml"
string(16) "stream-flush.xml"
string(15) "stream-lock.xml"
string(15) "stream-open.xml"
string(15) "stream-read.xml"
string(15) "stream-seek.xml"
string(21) "stream-set-option.xml"
string(15) "stream-stat.xml"
string(15) "stream-tell.xml"
string(16) "stream-write.xml"
string(10) "unlink.xml"
string(12) "url-stat.xml"
Rewinding..
string(13) "construct.xml"

Siehe auch

  • readdir() - Liest einen Eintrag aus einem Verzeichnis-Handle