PHP | getservbyport() Function

The getservbyport() function is an inbuilt function in PHP which returns the Internet service for given protocol and port number. Syntax:

string getservbyport( int $port, string $protocol)

Parameters: This function accepts two parameters as mentioned above and described below:

• $protocol: It is required parameter. It specifies the protocol name, like tcp, udp etc.
• $port: It is required parameter. It specifies the port number, like 80.

Return Value: This function returns the Internet Service name on success. Note: This function is available for PHP 4.0.0 and newer version. Below programs illustrate the getservbyport() function in PHP: Program 1: php

<?php

// Use getservbyport() function to get
// the Internet service which corresponds
// to port and protocol
$intservname = getservbyport(80, "tcp");

// Display the output
echo $intservname;

?>

Output:

http

Program 2: php

<?php
 
// Create an array of port numbers
$port = array(21, 22, 23, 25, 80);

// Loop run for each services
foreach( $port as $index) {
    
    // Use getservbyport() function to get
    // the Internet service which corresponds
    // to port and protocol
    echo $index . ": " .getservbyport($index, "tcp")
            . "<br>";
}

?>

Output:

21: ftp
22: ssh
23: telnet
25: smtp
80: http

Reference: https://www.php.net/manual/en/function.getservbyport.php