Returns whether the file is open. An open request can fail if a file cannot be found for example. This method lets you test that the open call succeeded.
Answer the current file position
| (offset) | 
 an offset in bytes.  | 
| (origin) | 
 one of the following Integers: 
  | 
Writes an item to the file.
| item | 
 one of the following:  | 
reads and returns a String up to lesser of next newline or 1023 chars.
read one byte and return as a Char.
read one byte and return as a Integer.
read two bytes and return as an Integer.
read four bytes and return as an Integer.
read four bytes and return as a Float.
read eight bytes and return as a Float.
Reads the next byte as an unsigned integer N, then reads the following N bytes and returns them as a String.
write a Char as one byte.
write an Integer as two bytes.
write an Integer as four bytes.
write a Float as four bytes.
write a Float as eight bytes.
write a null terminated String.
Writes aString preceded by its length represented as a single byte. Throws an error if aString is longer than 255 characters.
Writes aString followed by a zero byte, like a null-terminated C string.