12.6: Backspace
- Page ID
- 54329
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When reading from a file, each successive read will return the next line from the file. The computer keeps track of which lines have been read and will automatically return the next line. It is possible to read a line and then backspace and re-read the line again with the backspace statement.
The general form of a backspace statement is:
backspace(<unit number>)
Where the unit number was assigned during the initial open. The file must be open when the backspace is executed for the backspace to work. It should be noted that this operation is not used very often.