REWIND and BACKSPACE statements

These statements take the form :-

REWIND expression

BACKSPACE expression

where expression is the logical unit number e.g.:-

REWIND LUNIN BACKSPACE LUNOUT

The REWIND statement repositions to the start of the file (the name reflects the fact that originally files were held on magnetic tape). The BACKSPACE statement moves backwards through the file by one LOGICAL RECORD i.e. to the point in the file before the last READ or WRITE performed on it.