Linux – Temporarily Using a Different Home Directory

home

If it is possible, should be pretty basic, but I am puzzled how to ask Google the right question (or it is impossible).

Lets say we have

/home/user/
...conf
/home/user/candidate/
...conf

We have homedir and some subdir.. programs will use naturally from homedir(*/home/user*)

What I need is to temporarily change home user to */home/user/candidate*, so programs will call */home/user/candidate/conf*, instead */home/user/conf*

Now, I don't need usermod or anything else to change permanently /etc/passwd, i want to temporarily force programs to use my directory, thinking it is home, but on reboot fetch */home/user* and act normal.

Using */home/user/candidate* as home only session long, no usermod stuff.

Best Answer

You could use bind mount to make this redirection:

mount --bind /home/user/candidate/ /home/user/

This way, /home/user will show the contents of it´s subdir candidate. After making all you need, umount will destroy the binding:

umount /home/user/

More docs about bind mount:

Related Solutions

Clean $HOME directory

You can just temporarily displace them.

cd ~
mkdir .trash
find . ! -name . -prune ! -type d -atime +365 -exec \
    sh -c 'touch -a -- "$@"
           mv -- "$@" ~/.trash
    ' --   {} +

That will find all files in your $HOME directory - without recursing into child directories - which have not been accessed for a year. It will update the access time for all of them to right now, and then move all of them into a directory named .trash. If you encounter any problems between the time you run it and whatever time you decide to start deleting old files in ~/.trash then you can try moving some of them back and see if any of those you put in the trash were the cause.

.gnupg directory in the home directory

Most dot files have a name that resembles the application that uses it. Unsurprisingly, .gnupg is used by GnuPG. GnuPG (also known as GPG) is a program that encrypts and signs files. As soon as you invoke it for the first time, it will create a .gnupg directory in your home directory and a few files in it. This directory contains a lot of private information (e.g. who your contacts are), so it's accessible only to the owner. This could happen, for example, if someone sends you a signed email; if your email client supports PGP email then it will attempt to verify the signature (and fail since you don't have the sender's public key in your GPG keyring).

The real question here is why this directory in your home directory is owned by root. The answer is that you ran GPG as root, but with HOME set to your own home directory. Or, more precisely, you ran a program which ran GPG under the hood. One such program is APT: package management tools (apt-get, apt, aptitude, etc.) use GPG to verify that the packages that you download are genuine. If you ran something like sudo apt-get install SOMEPACKAGE, this would create a .gnupg directory in your home directory, since sudo doesn't change the home directory by default.

The fix is to remove the .gnupg directory, then create it under your user. You can just remove the root-owned directory (sudo rm -r ~/.gnupg): any file under your home directory is fair game for you. You could alternatively move it to root's home directory (sudo mv ~/.gnupg /root), but it doesn't contain anything important anyway. Then run a GPG command such as gpg --list-keys; this will populate your ~/.gnupg directory with empty keyring files.

Just entering a directory is always harmless. Listing files and viewing their content is usually harmless, but it can be harmful in some configurations because terminals parse escape sequences in what applications print. Under Linux, plain ls or ls -l is fine but ls -N is potentially risky. Plain cat filename is risky but less filename is fine (whereas less +R filename is risky). In the .gnupg directory, there's nothing harmful.

Best Answer

Related Solutions

Clean $HOME directory

.gnupg directory in the home directory

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