Copyright Digital Equipment Corp. All rights reserved.

ERR

 Identifies a branch target statement that receives control if an
 error occurs.  It takes the following form:

 ERR = s

 s  Is the label of an executable statement 

 ERR applies only to the OPEN statement in which it is specified,
 and not in subsequent I/O operations on the unit.  If an error
 occurs, no file is opened or created.  However, you can use IOSTAT
 in subsequent I/O statements to perform a similar function.