Issues with plotting progress ADS

[AGSPhoenix]

The :stream ADS used to save plot progress isn't well documented, causing issues when using non-NTFS storage systems.

• In some limited testing, creating the stream appears to silently fail on any non-NTFS partition, so trying to resume plotting just truncates the file and starts over without any confirmation.
• Windows Explorer will show a vague warning message when trying to move finished plotfiles to non-NTFS destinations: Are you sure you want to copy this file without its properties? The file <filename> has properties that can't be copied to the new location., followed by some general information about the file. New miners won't know they can safely ignore the message for finished plotfiles, but not for unfinished ones (I think).

These should at least be documented in the README. I think it would also be possible to adopt the resume system cg_obup uses, which indicates incomplete plotfiles with a magic number at the end of the file. If I understand the plotfile format correctly, this would allow either program to resume the other's plotfiles, and completely eliminate the handling issues with ADS streams.

Another option would be to delete the stream after plotting is complete, and don't try to resume on filesystems that don't support ADS. This would solve both of the above issues.

I'm not very skilled in C++, but I could put together a simple PR if you don't have the time.

[Blagodarenko]

"creating the stream appears to silently fail on any non-NTFS partition" fixed in v1.1 (sorry, I lost sources)

"These should at least be documented in the README" Yes, agree.

"which indicates incomplete plotfiles with a magic number at the end of the file" Xplotter create whole plotfile at start and then fill it, so filesize not changing while plotting.

[AGSPhoenix]

Xplotter create whole plotfile at start and then fill it, so filesize not changing while plotting.

Does that prevent you from saving plot progress to the file in the same way cg_obup does? Not trying to sound pushy, I just don't fully understand the plotfile format and how XPlotter writes it yet.