Cannot empty a string

Using Arduino Programming Questions
1

Hello, I read data from EDK (using Serial.available()). I seperate incoming datastream with a comma. If the program finds a comma the input string is cleared with: rx_byte = "";

When I append the next data item to another string, not only the read in data is appended, but also an "empty square" is printed in front of it.

Question: how can I suppress the "empty square"?

I enter the string:
four,five,six

The first item (four) is read properly, but the next two items (five and six) are suddenly preceded by a square.

Any one??

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2

Please read 'how to use this forum - please read' (there's a big clue in the title), then post your code and any output in the way suggested. Posting an image of text is daft.

3

When you post your program we will find out whether you are using strings or Strings