@Wildcard What do you learn about computers, and what do you become aware of that you don't know?

I am interested in CS, which is computer science.

Any thoughts on why a I might be able to mount a remote machine with sshfs, but ls hangs on the local mountpoint?

aliens

it freezes right after you mount it or after it's been mounted for some time?

Nothing freezes except the ls command, shortly after mount

Otherwise it appears nothing is wrong from mount and dmesg

can you copy files to/from it?

From trying just now cp to the local mountpoint doesn't return errors, but nothing appears on the remote server either

It just silently fails

so it seems like maybe an access issue

Scratch that, I had accidentally unmounted, when I remounted cp hangs as well

I am mounting sshfs as root btw, hopefully not an access issue :o

root@remote-host

My first thought was it was because I use btrfs locally and ZFS on remote machine, but loading ZFS kernel modules made no difference

sftp doesn't care what the filesystem is

Does it work with non-root users on the remote host?

I only have root setup to authenticate with this key at the moment

I'll try that

So it still happens mounting a non-root user's home directory

May be relevant that remote machine is FreeBSD, local is Linux? Not sure.

Do other FUSE filesystems work locally?

what about this? unix.stackexchange.com/questions/222944/…

Are you trying to access files with the same user as performed the mount?

That looks plausible

Though I'd expect EACCES rather than a hang

I don't have any other FUSE filesystems setup to compare against, unfortunately. Just tried using those permissions on mount, no changes. I have been trying to access as the same user performing the mount.

This is a silly thought, but maybe it's the sshfs mount itself that's failing? It ties up standard input instead of returning like a regular mount, but shows in the mount list so I've assumed it was mounted thus far

I am out of standard ideas then, might be a good question for the site

Alright, I appreciate your time and thoughts :)

@Rob sshfs usually forks to the background so that is a negative sign

sshfs -o LogLevel=VERBOSE may give some further hints

Or maybe you have to give a custom ssh command to include that, I'm not sure

Well this is pretty ridiculous, but I should've referred to my original question, which was authenticating sshfs with OpenPGP smartcard instead of a password.

I had started using -o SmartcardDevice=/dev/hidraw7 because this didn't bring up the password prompt

I'm not sure what changed, but I've tried not passing SmartcardDevice and it suddenly prompts for my smartcard at the shell

sshfs returns to shell now and ls/cp work

Hello. Quick question: What is "${do_quick_check-0}"? (via source.chromium.org/chromium/chromium/src/+/master:build/…)

@Rob that's a good place to use strace to see which system call exactly is hanging. Try strace -o /tmp/strace.out -f ls whatever and then look in /tmp/strace.out for the last few lines; that will show you what hung.

@deostroll see line 86 of the same script, and also unix.stackexchange.com/q/282807/135943 (or the bash man page on parameter expansion, specifically the few lines at the top if you run LESS='+/When not performing' man bash).

@Tim A lot. There are so many areas you can learn about, each one of which is a specialty field in itself. Algorithms and their proofs and space/time complexity; networking and the many various protocols; the kernel and its system calls and data structures; various programming languages and their nuances; databases and types of indexes; filesystems and their design tradeoffs; hardware and drivers; consumer end hardware comparisons; Linux distros comparisons and quirks; init and systemd...

...text encodings and locale/translation issues; open source software for various needs; cryptography and cryptanalysis; machine learning and AI; color gamuts and color space conversions; maths such as number theory and graph theory; instruction set designs and CPU pipelines; configuration management; software design workflows and collaborative strategies....

@Wildcard I see. Similar situation here. Thanks for replying.

@Rob Sounds like it still might be worth asking on the site, in the self-answered style. In case other people run into the same issue. Also, perhaps a bug report to ssh?

@Wildcard so is that an arithmetic expression?

@Wildcard ok figured out. I thought default values were always :-

Does a string like: 2020-08-07T19:13:13.765Z have any specific designation?