For people who wondering what the meaning of this function name:
pton: a presentation(printable) format address to network address
ntop: a network address to presentation(printable) format address
(PHP 5 >= 5.1.0, PHP 7, PHP 8)
inet_ntop — Konvertiert eine komprimierte IP-Adresse in ein menschenlesbares Format
Die Funktion konvertiert eine 32-bittige IPv4- oder eine 128-bittige IPv6-Adresse (sofern PHP mit IPv6-Unterstützung kompiliert wurde) in ein für die Adressfamilie geeignetes Format.
ipEine 32-bittige IPv4- or 128-bittige IPv6-Adresse.
Gibt eine Stringdarstellung der Adresse zurück. Bei einem Fehler wird false zurückgegeben.
Beispiel #1 inet_ntop()-Beispiel
<?php
$packed = chr(127) . chr(0) . chr(0) . chr(1);
$expanded = inet_ntop($packed);
/* Ausgabe: 127.0.0.1 */
echo $expanded;
$packed = str_repeat(chr(0), 15) . chr(1);
$expanded = inet_ntop($packed);
/* Ausgabe: ::1 */
echo $expanded;
?>
For people who wondering what the meaning of this function name:
pton: a presentation(printable) format address to network address
ntop: a network address to presentation(printable) format addressPHP's inet_ntop function is not compatible with the binary representation used by MySQL's INET6_ATON function, assuming you are using the recommended method of storing both IPv4 and IPv6 addresses in a VARBINARY(16) field. You need to convert it like this:
/**
* Convert a MySQL binary v4 (4-byte) or v6 (16-byte) IP address to a printable string.
* @param string $ip A binary string containing an IP address, as returned from MySQL's INET6_ATON function
* @return string Empty if not valid.
*/
function inet6_ntop($ip) {
$l = strlen($ip);
if ($l == 4 or $l == 16) {
return inet_ntop(pack('A' . $l, $ip));
}
return '';
}
You don't need a function going the other way because MySQL's INET6_NTOA is already compatible with PHP's inet_pton function.For people who need this function but don't have it, I could write a function which should give almost the same result.
<?php
function my_inet_ntop($ip) {
if (strlen($ip)==4) {
// ipv4
list(,$ip)=unpack('N',$ip);
$ip=long2ip($ip);
} elseif(strlen($ip)==16) {
// ipv6
$ip=bin2hex($ip);
$ip=substr(chunk_split($ip,4,':'),0,-1);
$ip=explode(':',$ip);
$res='';
foreach($ip as $seg) {
while($seg{0}=='0') $seg=substr($seg,1);
if ($seg!='') {
$res.=($res==''?'':':').$seg;
} else {
if (strpos($res,'::')===false) {
if (substr($res,-1)==':') continue;
$res.=':';
continue;
}
$res.=($res==''?'':':').'0';
}
}
$ip=$res;
}
return $ip;
}
?>
I followed IPv6 reprenstation rules :
- A series of "0"s in a 16bit block can by represented by "0".
- A series of blocks containing only "0"s can be suppressed and represented by "::" (this can be done only once)
(source : http://www.ipv6style.jp/en/faq/latest.shtml#2003022112 )
Example:
<?php
$packed = str_repeat(chr(0), 15) . chr(1);
$expanded = my_inet_ntop($packed);
/* Outputs: ::1 */
echo $expanded;
?>
I checked in CVS (2005-04-25) and didn't find the inet_ntop function (I really needed to handle IPv6) so I implemented it myself !