PHP | getprotobynumber() Function

The getprotobynumber() function is an inbuilt function in PHP which returns the protocol name for a specified protocol number. Syntax:

string getprotobynumber( int $protocol_number )

Parameters: This function accepts single parameter $protocol_number which is required. It specifies the protocol number, like 6 for tcp, 17 for udp etc. Return Value: This function returns protocol name on success and FALSE on failure. Note: This function is available for PHP 4.0.0 and newer version. Below programs illustrate the getprotobynumber() function in PHP: Program 1: This program uses protocol number for protocol name "tcp". php

<?php

// The getprotobynumber() function get protocol
// name associated with protocol number 
$protocolname = getprotobynumber(6);

// Display result
echo $protocolname;
?>

Output:

tcp

Program 2: This program checking for many protocol name. php

<?php

// Store the protocol number in an array
$protocol_number  = array(6, 17, 20, 41);

foreach( $protocol_number as $number ){
    
    // The getprotobynumber() function get protocol
    // name associated with protocol number 
    echo $number . ": " . getprotobynumber($number)
            . "<br>";
}
?>

Output:

6: tcp
17: udp
20: hmp
41: ipv6

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