getprotobynumber

Note that by the time of writing this note (5.3.3), there seems to be only two defined constants for the protocol numbers: SOL_UDP and SOL_TCP. For all other protocols (like ICMP,... ) you'll have to provide the exact number (EG: 1 for ICMP, ... )<?php    echo getprotobynumber(SOL_TCP) . "\n"; // prints tcp    echo getprotobynumber(SOL_UDP) . "\n"; // prints udp    var_dump(getprotobyname('tcp') == SOL_TCP); // bool(true)    var_dump(getprotobyname('udp') == SOL_UDP); // bool(true)?>On a UNIX system (don't know if this is true for Windows), the php functions getprotobyname and getprotobynumber are just wrapper for their corresponding system calls. These functions returns the protocol name or protocol number based on the definition from IANA. If you are looking for a protocol and you don't know its number, you can find the exact protocol number here: http://www.iana.org/assignments/protocol-numbers

getprotobynumber()=====================getprotobynumber() gets the protocol name for the given protocol number on the local system. If the protocol number is not recognized,the function returns FALSE.The given code snippet gives the list of protocols along with their protocol numbers=====================code<?$format = "number <---> protocol\n<br />";$format = "%6s <---> %s\n<br />";for($number = 0; $number < 255; $number ++) {    if (getprotobynumber ( $number ))                printf ( $format, " $number", getprotobynumber ( $number ) );}?>=====================OUTPUT:0 <---> ip 1 <---> icmp 2 <---> igmp 3 <---> ggp 4 <---> ipencap 5 <---> st 6 <---> tcp 8 <---> egp 9 <---> igp 12 <---> pup 17 <---> udp 20 <---> hmp 22 <---> xns-idp 27 <---> rdp 29 <---> iso-tp4 33 <---> dccp 36 <---> xtp 37 <---> ddp 38 <---> idpr-cmtp 41 <---> ipv6 43 <---> ipv6-route 44 <---> ipv6-frag 45 <---> idrp 46 <---> rsvp 47 <---> gre 50 <---> esp 51 <---> ah 57 <---> skip 58 <---> ipv6-icmp 59 <---> ipv6-nonxt 60 <---> ipv6-opts 73 <---> rspf 81 <---> vmtp 88 <---> eigrp 89 <---> ospf 93 <---> ax.25 94 <---> ipip 97 <---> etherip 98 <---> encap 103 <---> pim 108 <---> ipcomp 112 <---> vrrp 115 <---> l2tp 124 <---> isis 132 <---> sctp 133 <---> fc 135 <---> mobility-header 136 <---> udplite 137 <---> mpls-in-ip 138 <---> manet 139 <---> hip 140 <---> shim6 141 <---> wesp 142 <---> rohc

getprotobynumber()=====================getprotobynumber() gets the protocol name for the given protocol number on the local system. If the protocol number is not recognized,the function returns FALSE.The given code snippet gives the list of protocols along with their protocol numbers<?$format = "%6s %s\n<br />";for ($number = 0; $number < 255; $number++) {   if (getprotobynumber ($number))      printf ($format, " $number-->", getprotobynumber ($number)); }?>OUTPUT:0--> ip 1--> icmp 3--> ggp 6--> tcp 8--> egp 12--> pup 17--> udp 20--> hmp 22--> xns-idp 27--> rdp 66--> rvd