fixing multilogger so that v is properly nil instead of an empty slice if not specified

logging/funcs_file.go

@@ -11,14 +11,19 @@ import (
 func (l *FileLogger) Setup() {
 
 	var err error
+	var multi io.Writer
 
 	l.Logger = log.Default()
-	l.Logger.SetPrefix(l.Prefix)
+	l.Logger.SetPrefix(l.Prefix + " ")
 	if l.writer, err = os.OpenFile(l.Path, appendFlags, logPerm); err != nil {
 		log.Panicf("could not open log file \"%v\" for writing: %v\n", l.Path, err)
 	}
 	// https://stackoverflow.com/a/36719588/733214
-	multi := io.MultiWriter(os.Stdout, l.writer)
+	if l.EnableStdOut {
+		multi = io.MultiWriter(os.Stdout, l.writer)
+	} else {
+		multi = l.writer
+	}
 	l.Logger.SetOutput(multi)
 }
 
@@ -48,8 +53,9 @@ func (l *FileLogger) DoDebug(d bool) {
 
 // SetPrefix sets the prefix for this FileLogger.
 func (l *FileLogger) SetPrefix(prefix string) {
-	l.Prefix = prefix
-	l.Logger.SetPrefix(prefix)
+
+	l.Prefix = prefix + " "
+	l.Logger.SetPrefix(prefix + " ")
 }
 
 // Alert writes an ALERT-level message to this FileLogger.