Delete files after encryption.

[chrisidefix]

Generally, when you encrypt files, it might make sense to delete the original and only keep the encrypted version (this is probably not the default behaviour the users expect, but a regularly used one).

In this scenario - if you encrypt many files, it may make sense to allow crypto to delete these input files after encryption has finished (e.g. --delete or --remove). Of course the user could also do this manually, but it seems like a sensible option to include into crypto. @chrissimpkins do you think this feature would make sense?

Obviously it would also be important to make sure that the encryption was really successful as discussed in issue #13

And extending that thought - it would really be great to be able to securely delete this file (on users request), but I haven't seen a pythonic way to do this (OS X for example has an Finder option to Secure Empty Trash ..., but I don't think you can call this from Python :laughing:). Any ideas?

[chrissimpkins]

As an option like you suggest, I like this idea. Posted some information below for the development of this feature.

References:

Secure file deletion via Python on SO: http://stackoverflow.com/questions/17455300/python-securely-remove-file

srm:

srm --help
Usage: srm [OPTION]... [FILE]...
Overwrite and remove (unlink) the files.

  -d, --directory     ignored (for compatibility with rm(1))
  -f, --force         ignore nonexistent files, never prompt
  -i, --interactive   prompt before any removal
  -s, --simple        only overwrite with single random pass
  -m, --medium        overwrite with 7 US DoD compliant passes
  -z, --zero          after overwriting, zero blocks used by file
  -n, --nounlink      overwrite file, but do not rename or unlink
  -r, -R, --recursive remove the contents of directories
  -v, --verbose       explain what is being done
      --help          display this help and exit
      --version       display version information and exit

Note: The -s option overrides the -m option, if both are present.
If neither is specified, the 35-pass Gutmann algorithm is used.