1.76.3 FileStream: basic
- Private - Answer the offset from the start of the file corresponding
to the beginning of the read buffer.
- copyFrom: from to: to
- Answer the contents of the file between the two given positions
- Return the next character in the file, or nil at eof
- nextPut: aCharacter
- Store aCharacter on the file
- Return the next character in the file, or nil at eof.
Don't advance the file pointer.
- Answer the zero-based position from the start of the file
- position: n
- Set the file pointer to the zero-based position n
- Return the current size of the file, in bytes
- Truncate the file at the current position