REWIND

Statement: Positions a sequential or direct access file at the beginning of the file (the initial point). It takes one of the following forms:

Syntax

REWIND ([UNIT=]io-unit [, ERR=label] [, IOSTAT=i-var])
REWIND io-unit

io-unit
(Input) Is an external unit specifier.

label
Is the label of the branch target statement that receives control if an error occurs.

i-var
(Output)Is a scalar integer variable that is defined as a positive integer if an error occurs and zero if no error occurs.

Description

The unit number must refer to a file on disk or magnetic tape, and the file must be open for sequential, direct, or append access.

If a REWIND is done on a direct access file, the NEXTREC specifier is assigned a value of 1.

If a file is already positioned at the initial point, a REWIND statement has no effect.

If a REWIND statement is specified for a unit that is not open, it has no effect.

See Also

OPEN, READ, WRITE, Data Transfer I/O Statements, Branch Specifiers

Examples

The following statement repositions the file connected to I/O unit 3 to the beginning of the file:

REWIND 3

Consider the following statement:

REWIND (UNIT=9, IOSTAT=IOS, ERR=10)

This statement positions the file connected to unit 9 at the beginning of the file. If an error occurs, control is transferred to the statement labeled 10, and a positive integer is stored in variable IOS.

The following shows another example:

 WRITE (7, '(I10)') int
 REWIND (7)
 READ (7, '(I10)') int