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   // 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    // 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
