Don't compare with previous checksum value
Use perl module instead of external program
Add documentation of functions
Check more errors
Add function rewind

Not yet used
Add option to rewind tape at start
Update help information
Improve output
Reduce clean line width
Bug fix: improve output
Add new option: no rewind

No rewind tape between step
Miss to update help info
Bug fix: no rewind tape
Merge pull request #13 from Intellique/master

Update README.md
Merge pull request #1 from billy482/master

New fixes and features