ugBASIC User Manual

   ... = FREE

Retrieves the free space still available for strings, in terms of bytes. This is how many characters are still available to be stored. The maximum value when calling this function is that indicated by the DEFINE STRING SPACE statement. The default value for string storage is 1024 bytes. The command implicitly invokes garbage collection.

  PRINT FREE

 Fre

If you have encountered a problem using this command, if you think there is a bug or the explanation is unclear, please open an issue for this keyword on GitHub. Thank you!