Well, I did a little testing on Windows and found two things:
1) When you copy the file (using Command Prompt "copy" command), it copies the whole file (i.e., all streams).
2) a:file does indeed mean "file" on a floppy. I would assume that the code special-cases it if the thing before the : is a single letter.
Now, switching back to talking about Linux. Since there is no actual "copyfile" functionality in Unix/Liinux (there's just reading and writing a stream of bytes), it does seem that if you copy a file from an NTFS drive, using any of the usual tools (cp, cpio, rsync, etc), it will only get the unnamed stream - even if you have enabled the streams with the appropriate "mount" option (as detailed above). To get any of the other streams, you'd have to ask for it explicitly, which means in turn that you'd need a way to enumerate them. I don't know how to do that. So, it does seem like you just can't rely on Linux to be able to faithfully copy files to/from NTFS *if* streams are important to you.
Note, BTW, that I ask all this (and, in fact, this was the motivation for opening this thread) because I did recently do a massive copy from NTFS to NTFS on PiOs (on a Pi4 running Buster). After it finished, I began to worry about these issues - hence the post. I don't think any of my files actually depend on alternate streams, but, as I sort of alluded to in the OP, you never know what Windows is doing behind the scenes...
And, also as alluded to in the OP, NTFS does have other, shall we say, esoteric features. I wonder how well (if) these are handled by the Linux drivers.
1) When you copy the file (using Command Prompt "copy" command), it copies the whole file (i.e., all streams).
2) a:file does indeed mean "file" on a floppy. I would assume that the code special-cases it if the thing before the : is a single letter.
Now, switching back to talking about Linux. Since there is no actual "copyfile" functionality in Unix/Liinux (there's just reading and writing a stream of bytes), it does seem that if you copy a file from an NTFS drive, using any of the usual tools (cp, cpio, rsync, etc), it will only get the unnamed stream - even if you have enabled the streams with the appropriate "mount" option (as detailed above). To get any of the other streams, you'd have to ask for it explicitly, which means in turn that you'd need a way to enumerate them. I don't know how to do that. So, it does seem like you just can't rely on Linux to be able to faithfully copy files to/from NTFS *if* streams are important to you.
Note, BTW, that I ask all this (and, in fact, this was the motivation for opening this thread) because I did recently do a massive copy from NTFS to NTFS on PiOs (on a Pi4 running Buster). After it finished, I began to worry about these issues - hence the post. I don't think any of my files actually depend on alternate streams, but, as I sort of alluded to in the OP, you never know what Windows is doing behind the scenes...
And, also as alluded to in the OP, NTFS does have other, shall we say, esoteric features. I wonder how well (if) these are handled by the Linux drivers.
Statistics: Posted by BigRedMailbox — Sun Dec 29, 2024 1:21 am
