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problemsolution(s)notes
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you deleted a folder and recreated another folder with the exact same name, but you’re in the old folder- `cd $PWD` will cd to the new version of the folder (or `cd ../foldername`)
- `cd .` too
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you accidentally created a folder with literally 1 million files in it and now you can't list the folder, it takes like 2 minutes- use find | xargs or find -exec
- try `/bin/'ls -f -1` (unsorted, single column)
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even before you hit millions of files in a directory, you can easily have too many files for the maximum argument length to an executable- use find | xargs or find -exec
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navigate to a folder on an external volume, then that external volume goes away (eg the disk is unplugged)not sure what was meant by this tbh
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write to a mount point that isn't actually mounted at that time, then fail to find the apparently vanished file later (because it's been mounted over)- umount it to find the file
- (on Linux) get the file with a bind mount: `mkdir other; sudo mount -o bind . other; ls -l other/mountpoint`
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how '..' works when you are in a directory which you got to via a symlink: `cd ..` gives you a different directory than `ls ..`- `set -o physical` in bash will make them match
- `pwd -P` will resolve the path to the current dir (though this isn't really a solution)
- the equivalent of `set -o physical` in fish is:

functions --copy cd _fish_cd
function cd
if test "$argv" = "-"
_fish_cd -
else
_fish_cd (realpath $argv)
end
end		repro instructions:

cd ~
mkdir -p foo/bar/baz foo/bar/quux
ln -s foo/bar/baz .
cd baz # follows the symlink
echo $PWD # outputs ~/baz
ls .. # shows the contents of ~/foo/bar, not ~
cd ..
echo $PWD # outputs ~, not ~/foo/bar
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in bash: when I'm in a folder via a symlinked path and I try to tab-complete a ../sibling , it uses the real path during tab-completion and the symlink one when evaluating it. So you can end up in a situation where a path you tab completed doesn't existnot sure how to reproduce, would love ideas
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if you follow a directory symlink, you may not be able to backtrack- `cd -` (uses $OLDPWD in bash/zsh)not sure how to reproduce, would love ideas
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ls' is aliased to something with colour or other annotations that's really slow over a network share because it stat()s every file- in bash/zsh: `\ls` will bypass the alias
- `command ls` will bypass the alias
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what `mv file.txt dest` does is totally different depending on whether `dest` is a file or a directory (rename vs move to another folder)- you could try to get in the habit of typing `dest/` when you mean a directory, but this can backfire (see #14)
- for GNU mv: `mv -t dest source` will force dest to be a folder, `mv -T source dest` will force dest to be a file
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If you are using a FUSE filesystem and it hangs, you can end up with a black hole directory where any programs that touch it get stuck in "uninterruptable IO wait" which creates a spreading contagion that can make your system unusable until you reboot.- kill -9 the fuse process, then unmount
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`ls dir*` will list the contents of the directories, especially annoying if you just want to check where a symlink points to- use `ls -d`
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some things act differently depending on whether there's a `/` at the end, which can be confusing, for example:

- on Mac OS, `cp -R a/ b` will copy the *contents* of a to b, different from `cp -R a b`
- rsync		- rsync has a dry run option
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