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socketcand

Socketcand is a daemon that provides access to CAN interfaces on a machine via a network interface. The communication protocol uses a TCP/IP connection and a specific protocol to transfer CAN frames and control commands. The protocol specification can be found in ./doc/protocol.md.

Installation

To build and run socketcand make sure you have the following tools installed:

  • autoconf
  • make
  • gcc or another C compiler
  • a kernel that includes the SocketCAN modules
  • the headers for your kernel version
  • the libconfig with headers (libconfig-dev under debian based systems)

First run

$ ./autogen.sh

to create the 'configure' script.

Then run the created script with

$ ./configure

to check your system and create the Makefile. If you want to install scripts for a init system other than SysVinit check the available settings with './configure -h'. To compile and install the socketcand run

$ make
$ make install

Service discovery

The daemon uses a simple UDP beacon mechanism for service discovery. A beacon containing the service name, type and address is sent to the broadcast address (port 42000) at minimum every 3 seconds. A client only has to listen for messages of this type to detect all SocketCAN daemons in the local network.

Usage

 socketcand [-v | --verbose] [-i interfaces | --interfaces interfaces]
	[-p port | --port port] [-l interface | --listen interface]
	[-u name | --afuxname name] [-n | --no-beacon] [-d | --daemon]
	[-h | --help]

Description of the options

  • -v (activates verbose output to STDOUT)
  • -i interfaces (comma separated list of SocketCAN interfaces the daemon shall provide access to e.g. '-i can0,vcan1' - default: vcan0)
  • -p port (changes the default port '29536' the daemon is listening at)
  • -l interface (changes the default network interface the daemon will bind to - default: eth0)
  • -u name (the AF_UNIX socket path - abstract name when leading '/' is missing) (N.B. the AF_UNIX binding will supersede the port/interface settings)
  • -n (deactivates the discovery beacon)
  • -d (set this flag if you want log to syslog instead of STDOUT)
  • -h (prints this message)