getservbyname()

getservbyname() — Get port number associated with an Internet service and protocol.

Built-in function of PHP 8.5. The manual lists it as available in PHP 4, PHP 5, PHP 7, PHP 8. This page is the reference card: signature, parameters and return value, plus the changelog and the example the manual provides.

What it does

getservbyname() returns the Internet port which corresponds to service for the specified protocol as per /etc/services.

Signature

getservbyname(string $service, string $protocol): int|false

Parameters

Parameter	Type	What it takes
$service	string	The Internet service name, as a string.
$protocol	string	protocol is either "tcp" or "udp" (in lowercase).

Return value

Returns the port number, or false if service or protocol is not found.

Example

A runnable snippet:

$services = array('http', 'ftp', 'ssh', 'telnet', 'imap', 'smtp', 'nicname', 'gopher', 'finger', 'pop3', 'www'); foreach ($services as $service) { $port = getservbyname($service, 'tcp'); echo $service . ": " . $port . "<br />\n"; }