NAME

ip − internet protocol (IP) multiplexor

DESCRIPTION

ip is a (N by M) STREAMS multiplexor.  The upstream side (N) is clonable (see clone(7)) and normally linked under tcp(7), udp(2), and raw(7).  The downstream side is linked to various network interfaces, e.g. the ethernet interface et(7).  ip implements the IP protocol as well as the Internet Control Message Protocol (ICMP). 

COMMAND FUNCTIONS

ip recognizes the following ioctl commands. 

I_LINK Link another stream under ip.  I_LINK can only happen at channel 0 (the ip control channel).  Error codes are:

[EPERM] The user does not have the “root” privilege. 

[ENOSPC] Too many hardware interfaces have been linked under.  Resources are exhausted.  Currently the limit is set to 10. 

I_UNLINK Unlink the ip stream.  I_UNLINK can only happen at channel 0 (the ip control channel).  Error codes are:

[EPERM] The user does not have the “root” privilege. 

IPIOC_SETPROTO
Set the protocol number for input multiplexing. For the assigned number for a particular protocol, see <netinet/in.h>. 
When network data arrive at the ip(7), the protocol type (in the IP header) is used for input multiplexing.  If a match is found, data are sent upwardly to the matched stream.  If no match exists and the raw(7) multiplexor exists, data are then sent to raw(7).  Error codes are:

[EADDRINUSE] There is another ip clone already handling this protocol. 

FILES

/dev/ip ip clone device

/dev/ip0 ip control channel

SEE ALSO

streamio(7), clone(7), raw(7), udp(7), tcp(7), et(7)

September 02, 1992