Binary File Comparator seems to miss a difference

[mdruiter]

I have two large files, both 2,877,913,471 bytes of binary stuff. Only a few bytes differ between them, just after the start of the files: 1 byte at 0x23, and 3 bytes at 0x27.

When I use the File Comparator (that I cannot live without!), the first difference is found. But: the second is not! It is not in the Difference list, Alt-Down does not go there, and clicking on it also does nothing. However, the difference *is* highlighted (at least in the right pane, I cannot really distinguish the dark blue in the left).

If I truncate both files to under 2Gb, it does not happen: both differences are found.
I created two large files that have the same problem. I tried to attach them, but even 7-zipped both come larger than 1 Mb...

[Jan Rysavy]

Could you please email it to jan.rysavy@altap.cz?
Or use http://www.uschovna.cz/en/

Thank you.

[therube]

Assuming that this has to do with the (large) file size itself, this utility may help in creating a BIG FILE. (Which you could then make a simple byte change with a hex editor, or the like.)

BIGFILE.ZIP
Creates a large file with desired size; useful to force other files to the end of the disk, e.g. container files of compressed drives and temporary fill of drives >2GB to fix problems with install-software on very large drives with more than 2GB free space

(Now if I happened to have anywhere close to 4 GB of free disk space, I'd try it myself .)

[mdruiter]

I just e-mailed the files to Jan.
BTW, you do not need 4Gb of disk space, if you use NTFS compression: that saves almost half of it.

[Jan Rysavy]

Thank you!

[Jan Patera]

I have two large files, both 2,877,913,471 bytes of binary stuff. Only a few bytes differ between them, just after the start of the files: 1 byte at 0x23, and 3 bytes at 0x27.
When I use the File Comparator (...), the first difference is found. But: the second is not!

Uh, it took me a long time to notice that the window title says "... Computing Differences".
It is a feature by design that needs to be changed: When the files are being compared as binary, the first difference is found (and shown in the "Differences" combobox). Then the rest of comparing is moved to a background thread - you can (reasonably) work with the FC window while the remaining differences are being calculated in background. When *everything* is compared (i.e. all 4GB retrieved from HDD), the Differences combobox and window title get updated. I.e. it is not a question of less or more than 2 GB, but the time linearly grows with the size of the files.
The combobox should be updated on the fly. I will fix it for the next release of Salamander.

[mdruiter]

Ah! Great feature, but very much disguised... I think at least the combobox should say "Computing more differences" too.
Thanks for clarifying.

[Jan Patera]

The combobox should be updated on the fly.

Fixed for the next release of Salamander.