Default to system default path when using "protocol": "unix"

[briktop]

When logging via unix datagram sockets, you have to specify a path to write the logs to. It would be a great advantage if the library could find the system default syslog pipe by default.

Per my cursory investigation, this seems to be /dev/log in Linux, /var/run/log in BSD and /var/run/syslog in OSX. I would hope there is a reliable way to determine this at runtime.

[jhnlsn]

@briktop I'm working with nodejs v0.10.20 and 'unix' is not valid for

new dgram.Socket('unix');

the only valid values are udp4 and udp6, what version of node are you working with to get this to work?

[briktop]

Right, @johnymonster. winston-syslog depends on the unix-dgram package for this purpose. When protocol is "unix", this package is used to create the socket object: https://github.com/indexzero/winston-syslog/blob/master/lib/winston-syslog.js#L212