nesdev.org

Hi.

I have an external HD device to store my pictures and movies. I noticed that some movies (files are usually big) are not playing, but stopping & crashing, or doing weird things. I suspect that a copy into my HD isn't being made as it should be. Well, a friend of mine said about plugging it in an USB 1.0 port, but that's not the case as it seems...

Is there a program to copy and verify the file checksum/integrity after copying it???

Maybe try Robocopy? (It's part of Windows already.) https://en.wikipedia.org/wiki/Robocopy

rainwarrior wrote:Maybe try Robocopy? (It's part of Windows already.) https://en.wikipedia.org/wiki/Robocopy

Here's a front end for it:

http://www.upway2late.com/projects/winrobocopy

Or wait, does Robocopy actually have a verify feature? On closer look I don't think it actually does... It's been so long since I used it, I'd forgotten. Sorry.

You could always make an archive (tarball, zipfile, disc image, etc.), calculate a hash value, copy the file, and make sure the hash checks out.

Actually, it's not a good idea of zipping my pictures and movies, simply because I plug my HD & watch pics & videos in another PCs. So, I need a program that copies and checks (CRC?).

Teracopy will verify copied files if you ask it to.

Edit: Huh... maybe it's no longer free? I guess I have had it for a pretty long time.

Edit2: Okay, free for non commercial use. Pro version has features I wouldn't use. So recommendation stands I guess.

Rsync is the canonical command line lover's option; it apparently does verify all files it copies as well as not re-transferring things already on the target. ( stackexchange: does rsync verify files copied between two local drives? )

Wow, why have I never heard of rsync. Thanks lidnariq!

rsync = linux ?
Wanna Windows.

There's a Windows port: https://www.itefix.net/cwrsync

If you're comfortable without the GUI, there's builds of rsync in both Cygwin and in MSYS (both of which are *n*x-to-windows porting efforts, of varying levels of reimplementing a unixy environment). Interix is bundled with specific versions of Windows, which could let you build rsync for yourself.

Windows' built-in COPY.EXE does this via the /V flag (verifies results match the source). XCOPY.EXE also provides the same functionality (same flag). All this flag will do is verify that the data written at the destination matches that of the source. If your source is unreliable then you have a different situation to deal with.

If your source (i.e. reads) is returning I/O errors, then there's no point in bothering with generating checksums or any other comparisons because an I/O error is already indicative that your source cannot be trusted (i.e. restore from backups).

If you're just now doing backups, and are trying to do them off of media which is questionable (i.e. already returning I/O errors), then you should copy over what you can, and anything that returns I/O error should be considered lost / unusable. Otherwise if you have existing backups, then the software you used should -- if it's worth anything -- be providing you a way to back up only what's changed.

I can talk for days about this type of situation and how to "try" and recover from it (e.g. possibly make the hard disk usable / not return I/O errors going forward) since I do data recovery for the general populous, but I'm trying to keep it simple (avoiding discussing things like LBA remapping and so on).

rsync (something I use extensively) uses a checksum mechanism to both a) ensure what was copied matches the source, and b) to determine if anything has changed (i.e. comparing destination and source). I do not bother using rsync on Windows (I do not like MSYS/MinGW, and I hate Cygwin even more -- but if I had to choose between the two I'd go with the former) as there are some behaviours that I imagine NTFS and/or FAT/FAT32 cannot mimic (UNIX symbolic links vs. NTFS junctions vs. NTFS symbolic links (yes they are different!), for example).

Total Commander can do a post copy verify. http://www.ghisler.com/

you could use the command prompt(cmd.exe) and use "fc" it compares 2 files byte by byte. Just to see if your files are corrupted.

Try this command on one of your copied files. This assumes your file is named "file1.avi" and is on c:\ and your external drive letter is e:\.
"fc /b c:\file1.avi e:\file1.avi"