Fixes help to take an optional action as a value to get syntax for a given command

client.go

@@ -344,7 +344,7 @@ func (c *client) simpleCommand(action string) {
 	case "SEARCH":
 		c.search("", "", "?")
 	case "HELP", "?":
-		go c.Visit(helplocation)
+		c.Visit(helplocation)
 	default:
 		c.SetMessage(syntaxErrorMessage(action), true)
 		c.DrawMessage()
@@ -356,6 +356,14 @@ func (c *client) doCommand(action string, values []string) {
 	case "C", "CHECK":
 		c.displayConfigValue(values[0])
 		c.DrawMessage()
+	case "HELP", "?":
+		if val, ok := ERRS[values[0]]; ok {
+			c.SetMessage(val, false)
+		} else {
+			msg := fmt.Sprintf("%q is not a valid command; help syntax: %s", values[0], ERRS[action])
+			c.SetMessage(msg, false)
+		}
+		c.DrawMessage()
 	case "PURGE", "P":
 		err := c.Certs.Purge(values[0])
 		if err != nil {

cmdparse/parser.go

@@ -94,10 +94,10 @@ func (p *Parser) parseAction() (*Command, error) {
 	case Value:
 		cm.Target = t.val
 		cm.Type = DOLINK
-	case Word:
+	case Word, Action:
 		cm.Value = append(cm.Value, t.val)
 		cm.Type = DO
-	case Action, Whitespace:
+	case Whitespace:
 		return nil, fmt.Errorf("Found %q (%d), expected value", t.val, t.kind)
 	}
 	t = p.scan()

help.go

@@ -23,6 +23,6 @@ var ERRS = map[string]string{
 	"SET":       "`set [setting] [value]`",
 	"W":         "`w [target]`",
 	"WRITE":     "`write [target]`",
-	"?":         "`?`",
-	"HELP":      "`help`",
+	"?":         "`? [[command]]`",
+	"HELP":      "`help [[command]]`",
 }