ip(3): il protocol

sys/man/3/ip

@@ -1,6 +1,6 @@
 .TH IP 3
 .SH NAME
-ip, esp, gre, icmp, icmpv6, ipmux, rudp, tcp, udp \- network protocols over IP
+ip, esp, gre, icmp, icmpv6, ipmux, rudp, tcp, udp, il \- network protocols over IP
 .SH SYNOPSIS
 .nf
 .2C
@@ -29,6 +29,7 @@ ip, esp, gre, icmp, icmpv6, ipmux, rudp, tcp, udp \- network protocols over IP
 .B /net/rudp
 .B /net/tcp
 .B /net/udp
+.B /net/il
 .sp 0.3v
 .B /net/tcp/clone
 .B /net/tcp/stats
@@ -461,9 +462,11 @@ The possible items are:
 .BR ip ,
 .BR fs ,
 .BR tcp ,
+.BR il ,
 .BR icmp ,
 .BR udp ,
 .BR compress ,
+.BR ilmsg ,
 .BR gre ,
 .BR tcpwin ,
 .BR tcprxmt ,
@@ -515,7 +518,7 @@ The
 .I ip
 device
 supports IP as well as several protocols that run over it:
-TCP, UDP, RUDP, ICMP, GRE, and ESP.
+TCP, UDP, RUDP, ICMP, IL, GRE, and ESP.
 TCP and UDP provide the standard Internet
 protocols for reliable stream and unreliable datagram
 communication.
@@ -525,8 +528,8 @@ low level error messages and to implement
 .IR ping (8).
 GRE is a general encapsulation protocol.
 ESP is the encapsulation protocol for IPsec.
-IL provided a reliable datagram service for communication
-between Plan 9 machines over IPv4, but is no longer part of the system.
+IL provides a reliable datagram service for communication
+between Plan 9 machines but is now deprecated.
 .PP
 Each protocol is a subdirectory of the IP stack.
 The top level directory of each protocol contains a
@@ -930,6 +933,21 @@ must be executed before performing I/O on the corresponding
 .I data
 file.
 .
+.SS IL
+IL is a reliable point-to-point datagram protocol that runs over IPv4.
+Like TCP, IL delivers datagrams
+reliably and in order. Also like TCP, a connection is
+determined by the address and port numbers of the two ends.
+Like UDP, each read and write transfers a single datagram.
+.PP
+IL is efficient for LANs but doesn't have the
+congestion control features needed for use through
+the Internet.
+It is no longer necessary, except to communicate with old standalone
+.IR fs (4)
+file servers.
+Its use is now deprecated.
+.
 .SS GRE
 GRE is the encapsulation protocol used by PPTP.
 The kernel implements just enough of the protocol
@@ -1234,6 +1252,23 @@ datagrams sent
 .EE
 .PP
 Reading
+.B /net/il/stats
+returns a list of 6 tagged and newline-separated fields representing:
+.EX
+.ft 1
+.2C
+.in +0.25i
+checksum errors
+header length errors
+out of order messages
+retransmitted messages
+duplicate messages
+duplicate bytes
+.in -0.25i
+.1C
+.EE
+.PP
+Reading
 .B /net/gre/stats
 returns a list of 1 tagged number representing:
 .EX