.TH NETROM 4 "25 July 1996" Linux "Linux Programmer's Manual" .SH NAME AF_NETROM \- NET/ROM amateur packet radio protocol family .SH DESCRIPTION .LP .B NET/ROM is a protocol used extensively by radio amateurs. The Linux NET/ROM protocol family permits access to these protocols via the standard networking .B socket metaphor. .LP The NET/ROM protocol layer only supports connected mode. IP traffic may be stacked on top of NET/ROM frames using a non-standard extension to the NET/ROM protocol. .LP The only mode of operation is connected mode which is the mode used for a socket of type SOCK_SEQPACKET (stream sockets are not available in NET/ROM). This requires that the user ensures output data is suitably packetised, and that input data is read a packet at a time into a buffer of suitable size. .LP NET/ROM addresses consist of 6 ascii characters and a number called the SSID. These are encoded into a sockaddr_ax25 structure which is provided to the relevant system calls. .LP NET/ROM has some unusual properties. Notably in a multi-user system an AX.25 address is often associated with a user, and some users may not have such an association. a set of ioctl calls are provided to manage an association table. .LP NET/ROM supports the following socket options for SOL_NETROM. NETROM_T1 is the T1 timer in 1/10ths of a second, NETROM_T2 is the T2 timer in 1/10ths of a second. NETROM_N2, the retry counter is also configurable. There is no 'infinite retry' option supported however. It is possible for an application to request that the NET/ROM layer return the NET/ROM header as well as the application data, this is done via the NETROM_HDRINCL socket option. .SH "SEE ALSO" .BR call (1), .BR socket (2), .BR setsockopt(2), .BR getsockopt(2), .BR nrbroadcast (5), .BR nrports (5), .BR netromd (8), .BR noderest (8), .BR nodesave (8), .BR nrparms (8). .LP .SH AUTHOR Jonathan Naylor G4KLX