The rollback work statement rolls back (or undoes) a transaction.
rollback work {then|else statement.block}
This operation automatically undoes all updates made since the last begin work statement. All locks acquired within the transaction are released.
open "myfile" to f1 open "mylog" to f2 begin work write total on f2,timedate();* create synchronized log readu total from f1,"total" if total = 0 then rollback work;* Cannot do anything end else total = total - 1 write total on f1,"total" commit work else print "Could not update" end