I use sshfs, works great to let me drop files on my server from my
desktop. But I wouldn't call that "file sharing". I probably would call
that a "network disk" or "remote mount".
There's probably some formal definition out there, but when I think of
file sharing, I think of someone proffering up a single file (or folder)
and sharing it point-to-point with one or some small group of people.
I have long been plagued by the problem if sitting in a room or on a
boat with someone, 2 devices right next to one another, and no trivially
easy way to send a file from one device to the other without say first
uploading it to some mutual third party (e.g. whatsapp).
sshfs isn't going to let you share files between say 2 phones, at least,
not very easily if at all.
By recommendation further up in this thread, I tried Google's Quick
Share between my wife's phone and my phone. Followed all the
instructions, did not work. Followed all the troubleshooting
instructions. Nope, my device doesn't appear on her phone when I share,
and neither the other way around. Searched the web, found a ton of
people with same issue. It's DoA I'm afraid.
Between family members, we have in the past shared files using a
synology box and their Drive app. It works just like Dropbox except
file is on your own infra. It's not open source though and I don't know
how tied it actually is to Synology's infra. One certainly needs to be
on the net to use it.
To this day, I have yet ever to see an easy way to share a file between
2 devices without full internet connectivity, except by say getting one
to run an ftp or ssh server and ftp or ssh'ing over the file between
local ip addrs (e.g. 192.168.x.y). I'd love to know some well know
good, not-evil, open source app that runs on all the platforms that I
could tell people to install to send them a file without using the
internet. I can't really see any technical reason such an thing
couldn't work, say over bluetooth or local IPs and maybe it does exist,
I've just never run across such a thing. The key word here is EASY. I
can't be hacking someone's phone for an hour just to transfer them a
file.
Michael Grant