return No error for SYST:ERR:ALL? if no errors present, not just newline.

example/example.c

@@ -32,6 +32,9 @@ int main(void)
 
 	// test chardata
 	send_cmd("CHARD FOOBAR123_MOO_abcdef_HELLO, 12\n");
+	
+	
+	send_cmd("SYST:ERR:ALL?\n");
 }
 
 

source/scpi_builtins.c

@@ -158,14 +158,18 @@ static void builtin_SYST_ERR_ALLq(const SCPI_argval_t *args)
 {
 	(void)args;
 
+	if (scpi_error_count()) {
 		int cnt = 0;
 		while (scpi_error_count()) {
 			scpi_read_error(sbuf);
 			if (cnt++ > 0) scpi_send_string_raw(",");
 			scpi_send_string_raw(sbuf);
-	}
-
 			scpi_send_string_raw(scpi_eol);
+		}
+	} else {
+		scpi_read_error(sbuf); // O,"No error"
+		scpi_send_string(sbuf);
+	}
 }