I have a script on my ArcaOS system that I use to backup all of my logical drives, except those used by openSUSE, to a USB thumb drive. It works well except for drive M:, a rather large collection of manuals. The script uses zip, and when the archive file exceeds 4 GiB, unzip can't handle it.
unzip can definitely handle large files. Also the klibc based build can unarchive a compressed zip archive larger than 4GB. The problem with the private klibc build is a broken directory handling combined with file name and path length problems. Almost every program that is linked dynamically against libcxx has problems with root directories and codepages in general. But the LARGEFILE stuff is handled in a proper way on supported file systems. So in real world you can use it for single file zip archives larger than 4 GB without issues, but there will be problems with large directory sizes, amount of files or deep path structures.
I tried using -s and concatenating the pieces, but that just changed the symptoms.
Plan B was p7zip, with the command 7za w:\temp\M.7z M:\
I get a message that no files were found and an empty archive. I tried adding an * to M:\* and I tried the -r option; neither helped. What is the correct syntax for creating an archive of the entire volume?
A simple solution or workaround when files can cause trouble for crappy tools is to avoid the usage of files completely or to some degree. You can do simply a complete disk dump of this volume and piping it through a compressor to create a large file for recovery. Or you collect all names in the volume (by a dir or find utility) and check if names and path length can be handled by those tools you mentioned earlier.
as you seem to know exactly whats wrong with those so called private builds (even I have no idea why those should be called like that), I wonder where your bug reports are.
Exactly such ports give me the feeling I should completely give up on either reading anything in this forum at all, or give up completely with porting software.
Just pointing to software which should not behave right, but not adding bug reports is not the way to go. Sorry