ACUCOBOL-GT solves this problem by providing a transaction logging facility. All file operations that are part of a transaction are logged. Once logged, they can either be committed or rolled back (undone) by the program.
If a program dies, or the system fails, the log file can be used to reconstruct complete transactions, thus returning all files to a consistent state.
Transaction logging thus offers these two facilities:
It provides the programmer with the ability to define transactions, and the
ability to commit them or "undo" them (usually in response to an error condition). This "undo" facility is called a "rollback."
It provides the ability to reconstruct files into a consistent state after a
program dies or system failure occurs. This operation is called "recovery."