logrotated can be configured to send a SIGHUP signal to a process after rotating it's logs. This library reopens the underlying os.File when a SIGHUP is received by the app.
This is will enable all log calls to output to the log file without interruption when logrotated rotates the file.
logfile, err := logrotate.NewFile("/log/path/here")
if err != nil {
log.Fatal(err)
}
log.SetOutput(logfile)
ref: http://linux.die.net/man/8/logrotate
Notice the capitalization!
go get github.com/NYTimes/logrotate